Hi,
Frankly, there are "good", "mediocre" and "poor" quality flat bed scanners.... And there are also good, mediocre and poor quality dedicated film scanners.
You can spend <$100 to $1000> on a flat bed.... basically getting what you pay for.
Likewise you can spend <$100 on a "junk" dedicated film scanner... or $10,000> on one like pro labs use.
I can't find very detailed specifications on the all-in-one (scanner, printer, fax) you've got. But, generally speaking the scanner portion of those do a fairly modest job. From a good 35mm color negative or slide, you will probably be able to make a scan good enough to make a 4x6" or 5x7" print. Likely you will need to retouch the image quite a bit, for dust, scratches, etc. Anything on the slide or neg will be magnified.
When used for 35mm and smaller film formats, flat bed scanners are not as good as quality, dedicated film scanners. With flat bed scanners there is always a layer of glass between the lens and the image. That's like taking photographs through a window. Flatbeds are designed to copy documents with little magnification.... 1:1 most commonly. A dedicated film scanner directly images the film itself and is designed for high magnification. The MG8120 specs cite 4X magnification of documents. In comparison, an 8x10 made from 35mm film is approx. 8X enlargement... and 11x14" print is around 11X. Dedicated film scanners use one or more high quality macro lenses. It's unlikely the lens quality of a flatbed is anywhere near as good.
I couldn't find any information about the dynamic range of your scanner. Most flat bed and all-in-ones are pretty low.... have a D-Max below 3. The most ideal is 4 and most dedicated film scanners are in the 3.5 and higher range. Dynamic range of the scanner effects how much highlight and shadow detail will be captured from images.
Your MG8120 specs claim 4800 x 9600 ppi and 48-bit color depth, both of which are good.
Flat bed scanners can work pretty well with medium format and large format film, where far less magnification is required.
But you are also likely to see some problems trying to scan silver halide B&W film. The reason for this is because of how that film... the type that you can pretty easily develop yourself at home... works and is constructed. Light sensitive silver halide is suspended in an emulsion on a film transparent base. The more light that the silver halide is exposed to, the more and larger silver crystals form to block light. The development process sort of "locks" th ose silver crystals in place, where they will serve to block light passing through the film, creating the image. As a result, the negative is created. Later when you make a traditional enlargement from a negative you project a strong light through the film onto paper that has a similar silver halide emulsion, on a white paper base.
But when you scan the film instead, light is transmitted through it without that enlargement and it's essentially highly magnified.... The result is a "contrasty" looking scan, where the two extremes of highlights and shadows lose detail due to the way the light is either blocked or allowed to pass through the neg. This makes the images look "clipped"... as if you used a "high key" method shooting the image and then printed it on extremely high contrast paper. Less like a photo and more like a line drawing or illustration. Magnifying that's inherent in the film scanning process also greatly amplifies the appearance of grain in the neg.
On the other hand, instead of using silver halide crystals to form the image, color negative, slide films (transparency) and chromogenic B&W film all use dyes. Those don't "block" light... they allow some to pass in all areas of the image, in a more linear manner that makes for a much better scan. Better highlight and shadow detail... or less "clipping" at those extremes.
B&W chromogenic negs tend to look somewhat flat and low contrast when printed traditionally, but thanks to the dyes used will scan much better than silver-based B&W negs.
Problems are...
1. There isn't a lot of choice of chromogenic B&W film. Last time I looked, only Ilford XP2 was still being made in 35mm and medium size formats.
2. Chromogenic B&W film isn't practical to develop at home. It's developed using the C41 process, the same as color neg film. The same process most 1-hour labs have used for many years. While this is still fairly widely available, it's not anywhere near as common as it was in the past and the process involves a lot of chemistry and temperature controls that are well beyond the capabilities of most home darkrooms.
In fact, I think you should
go ahead and use what you've got, do the best you can with it and see if it meets your purposes. I'm really not trying to discourage you from trying it. Just letting you know that there are likely to be some "issues", why they occur, and what you may or may not be able to do about them.
I've scanned images for 20+ years.... Not much lately, since I mostly just shoot digital now. But most of my scanning was 35mm color transparencies, some color negs and a few 35mm B&W chromogenic... with a dedicated Nikon film scanner. One of the reasons I chose that particular film scanner was an accessory available for it that allows me to load up as many as 40 mounted 35mm slides and let it run overnight. It also can be set to scan all the images on cut 35mm film strips or even an entire uncut roll of film.
I have far fewer of them, so medium and large format film I scanned with a flatbed or had professionally scanned rather than invest in a super high priced dedicate film scanner capable of handling larger sizes of film.
I no longer have it, but I used an Epson V-series flat bed. I forget which models.... The current Epson V800 and V850 are their top-of-the-line. The previous V700 and V750 are similar, but not as fast. The V600 is okay, but has much less dynamic range. The V550 is their most budget version, rather marginal even for medium format film scans.
With the dedicated film scanner I had little trouble making high quality 8x10" and 11x14" prints from slides and color negs.
With the flat bed and medium format film I was able to make high quality 11x14" prints, too.
My flat bed also served to scan B&W
prints. This is the best way to digitize a silver-halide B&W neg image. First make a high quality, traditional, chemical darkroom enlargement from it, then scan that on a flat bed. I tried scanning B&W negs directly, but the results weren't up to my expectations. Scanning an enlargement instead was much better... But, of course, handling B&W images this way requires a darkroom complete with enlarger, etc.
I sold off my old flat bed, after I finished scanning the relatively few B&W prints and medium/large format film with the flat bed, . It also took up a lot of space, which I don't have to spare right no
Regarding software...
Silverfast is excellent scanning software. HOWEVER, it is scanner-specific and they don't make a version for Canon MG8120 that I can find. This is another problem with scanners of this type. The better software doesn't support them. The Canon scanners that Silverfast supports are all flat beds (not all-in-ones): 5600F, 8600F, 8800F, 9000F, 9000F Mark II, 9900F, 9950F, FS4000US. Even if you had one of those Canon scanners that can use it, Silverfast SE 8.8 and SE 8.8 Plus are the more affordable and less advanced form of Silverfast scanning software, selling for around $40 and $90 respectively. That's fairly basic software, probably not a great deal better than what came with your printer/scanner. The really "good" and advanced Silverfast AI Studio and AI Studio SE start at $225 and can cost well over $1000 a copy with some of the extensions. But this is all a moot point, since Silverfast doesn't support your particular scanner (or any other "all-in-one" I'm aware of). They do make versions for Epson V-series scanners (as well as for my dedicated Nikon)
https://www.silverfast.com/If needed, a more practical "generic" software that works with most scanners is Hamrick "Vuescan"... It sells in standard and pro versions for $50 and $100, respectively. I don't know if this is "better" than what Canon provided with your scanner. I have Vuescan installed now, for occasional use with my Nikon film scanner. It works pretty well.
https://www.hamrick.com/Again, try to use what you've got... But be aware of the possible alternatives, if you feel they might be needed.
Below are a few images I scanned and happen to have online for reference... all from 35mm film w/dedicated scanner... which have been printed 8x10 and 11x14: