If you're a book fan you will always be behind with new function. I don't know what youtube you are following but I use Anthony Morganti. He has an entire set of well done videos of the basics, advanced and if you sign up for his Email a weekly newsletter with short videos on what gets changed or fixed in the service stream. He covers LR/PS, On1, Luminar, NIK, Topaz etc. The tip his stuff starts at https://iammrphotographer.com/.

Most of the videos are relatively short and devoted to a specific topic such as tools, import etc.

A number of years ago, after much frustration with Nikon's software products, I made it my mission to learn Lightroom, and I have been a very happy camper ever since. I use Lightroom for 95% of my work and Photoshop for the other 5%. It works well for me and, over time, I have become more and more efficient using this workflow and a hardware add-on called Pallete Gear. I bought a book from Kelby @ Lightroom, but it was when I purchased and watched the video series from Laura Shoe that I really was able to begin my immersion into Lightroom. Best $100 I ever spent! It is critical to have a solid plan for naming and storing files BEFORE you begin using Lightroom going foreword. Best of luck.

There are some online courses, some of which are free, but I find them hard to follow. Listening to the video, i t all sounds good until you go to do something and try to remember everything step by step. I wish there were a place where things were laid out in written text with pictures, all in step by step fashion. If there's anything like that out there I haven't found it.

We used to have a place called Learning Exchange in our town. Instructors would rent small classrooms and teach all aspects of photography and even Light Room. Unfortunately that place which was owned by a private businessman, closed a couple of years ago. I took a series of six three hour courses on Lightroom there. It was invaluable. If you can find something similar in your community it's a great service. Maybe a community college?

The thing that makes LR so hard to understand is that it's not just one thing. It's a database (to organize your files) and it's also a post processing application. To make it even more confusing Adobe has another product called bridge which is also a database program.

The other thing about LR is that for every operation there are three or four different ways to perform it. In that way it's a lot like AutoCAD if you've ever used it. It's great to have 4 different ways to approach brightness and contrast, for example, but it's confusing for a beginner. If I were ambitious, which I'm not, maybe I would write a book on beginning Lightroom. Maybe a catchy title like "Lightroom for Dummies" or "Lightroom for the Soul."

When I got my first digital camera - a Nikon D70 - around 2004, I was disappointed with the results SOOC, and a friend recommended Photoshop; there was no Lightroom at the time. I got a copy of PS, and found a book called "Adobe Photoshop CC Classroom in a Book." It came with a CD of images to work on; as I read the book, I used my PS on the CD images as directed, and learned the basics. Amazon has the 2021 version for $27.53.

I never finished the book, as it began to get into things I had no interest in, but I learned how to do most of the basics, so I could get the image through Camera Raw, crop, do selections, and work in layers; you may not know what I'm talking about there, but the upshot has been pretty satisfying. Of course, I'm learning new things all the time, using the sorts of resources already discussed in this thread, and sometimes just poking around in PS, trying options I don't know about, often to good effect. But I got rolling with the Classroom In A Book.