Tried use GIMP a few times, but the standards feels way too different from Photoshop.

Because it is different.

and GIMP is nearly impossible to use for me.

As long as you wish it to become Photoshop-like, it will remain ‘impossible’. Bu the moment you agree that it is not some free clone of Photoshop but its own thing, it starts becoming… not impossible. And I say that as an almost 60 years old dude that had been using Apple computer since the early 80s and purchased and started using Photoshop for my job in the late 90s, that is now using GNU/Linux full time.

Imho, the best way to learn Gimp, or any new software, is not to wish for it to be more like Photoshop (or any other software you may previously used) but to start using it… from scratch and to do it progressively.

Don’t try to master it or to reach the same level of expertise you have under Photoshop (this took you probably a few years, at the very least a few months… and I’m sorry to say there is no shortcuts: learning takes time. But if you give yourself small specific tasks to learn to do you will quickly see yourself getting better… faster and faster.

Not knowing what you used Photoshop for it’s hard to suggest anything but say you used to it to edit your photos. Make a list of all the things you used to do, not the tools you used to use under Photoshop just the task you want to achieve. And start learning them one at a time.

Say, learn to crop and to resize a picture. Next time, learn to change file format or to color correct. Learn to change exposition or use curves. Learn to use masking tools to do local edits, use layers, and so on.

You will also realize there are tools you used to use that have no equivalency under Gimp. And that there other tools that exist under Gimp. But learning the tools and methods one at a time will make it much simpler:

1. you won’t need to be looking in those endless menus with their endless options all at once, nor to learn all the keyboard shortcuts (that is essential to learn if you want to be more efficient, like with any app worth something)
2. you will only need to search for specific tuto or guides, asking precise questions: ‘how do I change gamma in Gimp’ ‘how do I change color balance’, ‘how do I crop’, and so on… that are more likely to bring you much more useful results than broader questions like ‘how do I learn to use Gimp as a previous Photoshop user’ ;)

edit: typos