I forgot to mention... "Arca Swiss" is a manufacturer themselves, making tripod heads and other related products. Any search you do using "Arca Swiss" terms will turn up their products, as well as many other brands. The company Arca Swiss invented their quick release system, but has seen it widely adopted by many other manufacturers. For example, I just did a search for tripod & head "kits" at B&H Photo and found they list 324 tripods using heads with an Arca-compatible quick release platform (some of which come with one generic plate, too). Prices range from $60 to $1550!
If you already have a tripod you have a several choices...
1. If the head on it has the standard 1/4" screw to mount cameras, get an Arca adapter like I used and show in photo #1 above. If you go this route, I recommend after fastening the adapter to the head, drill a second hole and tap it to install a set screw to "lock" the adapter in place. (The adapter I bought has two additional, threaded holes already. I just need to find some set screws to fit it.)
2. If the head on it has some other type of quick release, get an adapter that "converts" it to Arca adapter. I'm wary of doing this because it seems like a possible point of failure.
3. If the head on it allows, it may be possible to remove the existing camera mounting platform and replace it with one that's Arca-compatible. I did this with a Manfrotto ballhead some years ago. It had one of their proprietary QR platforms, but that simply unscrewed. Kirk Photo made an Arca quick release compatible platform that simply screwed on to replace it. That wasn't cheap... if I recall correctly, about $75 at the time and probably more than that now. Because I wanted a safe and secure ballhead, I used some red Locktite on the threads to make it a permanent fastening. (Note: red Locktite makes a threaded fastener pretty permanent and largely un-removable... blue Locktite should be used when parts may need to be removed later).
4. Entirely replace the head on your tripod with one that's already set up with an Arca-compatible platform. The vast majority of tripods of any quality at all use a standardized 3/8" threaded bolt to fasten the head to the tripod and simply unscrew. Some (like Manfrotto) also use some sort of set screw(s) to lock the head in place on the tripod. Those have to be loosened before it can be unscrewed. If you decide to replace the head entirely, you'll have choice of a variety of types that come already fitted with the Arca platform: ballheads, pan-tilt, fluid, pistol grip, gimbals and more. They also come in a wide variety of sizes and capacities, plus vary in a number of other ways.
If, instead you want a second complete tripod you can either buy a ready assembled kit of legs and head or buy those (and possibly other) components separately.
Just for example, below link is to a search of complete tripod kits at B&H Photo, all of which appear to have heads with Arca-Swiss compatibility. Shop wherever you like. I'm just referencing B&H because they stock practically everything!
https://www.bhphotovideo.com/c/products/Complete-Tripods-with-Heads/ci/2635/N/4075788742?sort=PRICE_LOW_TO_HIGH&filters=fct_quick-release-system_7375%3AarcaOf course, you'll need to look at a number of other important factors among those tripods. In general, you'll want to consider the materials, height, design features, weight and load capacity of tripods and heads all vary quite a bit. Use the search filters at B&H or elsewhere to narrow it down.
Some will tell you, and they're correct, that "weight rating" tripods and heads is pretty inexact. Weight ratings are just what the manufacturer claims and aren't really the best way to determine the stability and usefulness of a tripod. This is true... But, weight ratings are pretty universally used and pretty much all we have to compare tripods with each other. Just look for a tripod that has "more than enough" weight capacity. Personally, I don't think I'd ever buy a tripod or head rated for less than 20 lb., even though most gear I use on it weighs half or one quarter that much. What I use is rated for at least 30 lb. and some of it up to 50 lb.
The most stable tripod has as few leg sections as possible and doesn't rely upon a center column to bring your camera up to comfortable working height. What is a comfortable height? Measure your eyeline and look for a tripod that will bring your viewfinder eyeport at least that high and maybe a couple inches higher. Obviously you have to compromise since you also need a tripod to fold up reasonably compact. Carbon fiber is arguably the best material for tripods. It's strong, saves weight, make for good rigidity and even absorbs some small vibrations. But it's also more expensive than aluminum.
Other "stuff" can be important. Personally I try to keep to three-section legs when possible, four-section only when I must and never any more than that. And I avoid tripods with columns that rotate to horizontal because that's another possible point of failure and using them with the camera hanging way off to the side is pretty unstable. It's probably not as important, but I also generally would avoid tripods that have one leg removable to be used as a monopod. That's another possible point of failure and may affect stability, but also any tripod can be used "like a monopod", simply by only extending one of it's legs. A lot of tripods with a built in monopod also have extra sections in the center column that have to be extended to bring them to a comfortable height, but really compromise stability.
I'm also picky about leg locks... prefer the "twist" type which are self-adjusting and generally work well. I don't care for the lever type, which are prone to wear and breakage, needing adjustment and repair. Thumb screws are okay, in my opinion, but because they protrude and can catch on branches, sleeves, etc. I leave tripods with that type of leg lock "in studio".
Best tripod advice I can give you: Don't buy "too cheap". If you do, you'll be buying a replacement in a year or two when it fails or just doesn't work well... then again a year or two after that... and another a year or two later, etc. It's false economy. A good, quality tripod may cost more but can last a lifetime. I've got one that I bought new and have used for close to 40 years. That's a big heavy tripod though and I ain't gettin' any younger, so I don't take it in the field anymore. About 20 years ago I bought my current, most-used tripod that still goes with me on almost every shoot. It's carbon fiber and close to half the weight of my older tripod. Both have three-section legs, are more than tall enough for me that I don't need to raise a center column (in fact one doesn't even have a center column), are rock steady with even very large (8 and 10 lb.) lenses and have been used hard all these years without any problems at all. (Some other tripods I have are similar age, but I bought them used more recently. Occasionally I stumble across just too good a deal to pass up, like the $10 Bogen in the photos above.)
Going too cheap on a tripod also often leads to disappointment, which discourages you from taking the tripod with you and using it regularly. A quality tripod that's reliable and comfortable to work with will be more of a pleasure to use and will hold up well... and be less likely to be left at home in a closet.