Einstein: His Life and Universe https://toptalkedbooks.com/amzn/1501171380
The World As I See It https://toptalkedbooks.com/amzn/1494877066
I recommend those two, also, one of Richard Feynmans books talks about Einstein. They were colleagues. It's also just a great book, definitely recommend.
Surely You're Joking, Mr. Feynman!: Adventures of a Curious Character https://toptalkedbooks.com/amzn/0393355624
For anyone who hasn't read "Surly you're joking Mr. Feynman" , you should. Highly recommended.
I was in the same boat recently. I joined STEM mainly because I inspired by the greats (Feynman, Sagan, Hawking, and so on) that I grew up watching and reading about. They explained the big ideas and I got all excited and wanted to solve them. Over the years I got to into the weeds, fatigued, lost passion, and forgot about why I joined STEM. You just have to find that same passion that made you pursue STEM in the first place again.
Honestly everyone goes through this. Richard Feynman went through this and was "disgusted" with Physics. After doing some soul searching he rediscovered why he loved Physics again. He talks about this in a book of his "[Surely Your Joking Mr.Feyman]([https://toptalkedbooks.com/amzn/0393355624) )" and there's a youtube vid somewhere but I can't find it for some reason.