answering your tags, I haven't read any of Brandon Sanderson's books yet, but he teaches a sci-fi/fantasy creative writing class that's on youtube and been highly recommended. have you read from him, if so what did you like the most?
yes i am a Big Fan of his — it is probably more accurate to describe me as a fanatic. I just tried to go through his list of works to see which i've read and which i own, and while i wasn't able to get a solid count, I've read most of them and own a fair amount.
the thing to understand about recommending any of Sanderson's books is that the vast majority of his works are set in the same overarching universe, called the Cosmere. While different series are (usually) set on different planets, the magic systems all follow an overarching set of rules, and as the Cosmere continues, we're going to see more and more crossover. that being said, you can read almost all of his currently published books without knowing the wider implications. so with that said, I recommend starting with either The Emperor's Soul or Tress of the Emerald Sea.
I've been suggesting The Emperor's Soul to people for years as a gateway to Sanderson's work, for a couple of reasons. First, it's a novella (I think somewhere around a hundred pages?) rather than some of his gargantuan other works (multiple of his books are over a thousand pages). Second, I think it has a really cool magic system, which I feel is one of Sanderson's strengths. Third, it won the Hugo Award for Best Novella, so I have some critics backing me up. And last but most definitely not least, I really like it. Which is always something you should look for in book recommendations!
Tress of the Emerald Sea was one of the "Secret Novels" Sanderson wrote while quarantining during the pandemic and published through the biggest Kickstarter of all time. Although I still haven't gotten my physical copy, I read my ebook copy on New Year's Day, the day it came out, and I really loved it. The inspiration for it was "What if, in The Princess Bride, Buttercup goes after Westley to rescue him?" It was a very fun read that, like The Emperor's Soul, teases connections to other Cosmere books without relying on you having already read them. This book also has a cool magic system, but even cooler is the worldbuilding, which I think is Sanderson's greatest strength.
I'll also point you to Sanderson's page on where to start.
As for my favorites, the two above are probably my two favorite single stories of his, but I also love The Stormlight Archive (epic fantasy) and Elantris (because the magic system is like programming) and Mistborn because the magic system is cool in a different way and Warbreaker because of the humor and
I like pretty much all of his work. Sanderson's works are also varied enough that even if you don't like any of the above works, you may still like some of his other works.
If you have any other questions, please do ask me — clearly, I love talking about them (and books in general).
Also, just because I love how Sanderson announced his Secret Novels, here's the video: