Jealousy is a huge motivator. Having to do something for a purpose is even better. What do you want to do? Because the endeavors you mentioned don’t happen overnight. When your sitting at your desk solving some problem that you didn’t even anticipate and you’re not even doing that thing you set out to do, it’s hard to stay motivated. So, what is it about those endeavors that you mentioned piques your interest?
Just do it! I would suggest just start writing. Editors and technology can help you cover some of your issues. What sort of books are we talking about? 200+ page nonfiction? IMO writing a book is an endeavor.
Find a platform somewhere and write short stories, whether it be your family and friends or somewhere on the Internet. Check out https://lemmy.world/c/writingprompts (even bigger on Reddit). Write blog posts. Write write write. Maybe exploring those partial ideas. Collect all your writing in one area so that you can look back at it and see progress.