Do you have a library card? At my library I can reserve the books I want, and if they don’t have them they borrow them from another library in their system, and I get an email when they’re ready to be picked up. I also use the app Goodreads to track what I want to read.
If reading physical books is difficult, consider audiobooks as well!
For something sci fi/fantasy but more a serious/intense story:
Do you have a library card? At my library I can reserve the books I want, and if they don’t have them they borrow them from another library in their system, and I get an email when they’re ready to be picked up. I also use the app Goodreads to track what I want to read.
If reading physical books is difficult, consider audiobooks as well!
For something sci fi/fantasy but more a serious/intense story:
A Deadly Education / the Scholomance series
Project Hail Mary
For more feel-good sci fi/fantasy:
The House in the Cerulean Sea
A Wizard’s Guide to Defensive Baking
The Long Way to a Small, Angry Planet