Hello @Zombifiedkitten, and welcome to the forum!
I can only suggest watching the tutorials made by @CelticCoco, a.k.a. Blade & Quill on YouTube, Corinne offers a wonderful door into the world of Krita:
https://www.youtube.com/@BladeandQuillartacademy
Of course, the YouTube-Channel of Krita itself offers a lot of information on different aspects of Krita:
https://www.youtube.com/@KritaOrgPainting/playlists
And one of my beloved tips is a tutorial series that is originally geared towards kids, offers its lections in easy digestible bits of ~5 minutes length and if you can bear and accept the fact that the intended audience is kids, you will perhaps love this series as I do. Especially for users who may have learning disabilities, like ADHD, or are a dyslexic person, these vids can be the material they searched for, at least I loved watching the 35-parts it lasts:
35-part Krita course for kids, but I think not only suitable for children
For brushes, you should start with those Krita offers before you dive into the ocean of brushes made for Krita, and to hear this from me, a brush addict really should give you to think. If Krita’s brushes won’t offer what you are looking for, you can crawl our resource category, and if even that is not enough, I can name you a lot of sources you can not find here.
Michelist