Reddit reviews Jazz Improvisation: Tonal and Rhythmic Principles

I think John Mehegan's books on Jazz Piano were really excellent in helping me build my skills.

https://www.amazon.com/Jazz-Improvisation-Tonal-Rhythmic-Principles/dp/0823025594

I'm not clear if you've transcribed the changes, melody or both. If you get stuck just ask; after several decades of doing this kind of thing it's really easy for me.

IntoEternity mentioned that this is hard, and yes, it probably is. I learned the system of Roman numerals for changes when I was 18 from Jerry Coker's book Improvising Jazz. Another book, less user friendly IMO, is John Mehegan's Jazz Improvisation. As others have mentioned you'll probably need to get comfortable with the chord sequences of simpler standards to start with. Autumn Leaves is a good one because it's basically in one key, which is actually rare for most standards.

One issue that you will need to sort out fairly soon is understanding basic jazz harmony. The problem with many fakebooks, including the Real Book, Aebersold charts, and Chuck Sher's New Real books is they often give you too much information. Chick Corea said that he writes chord symbols as major, minor, or dominant 7th, because he says it's easier to convey the tune, and if a player doesn't know how to interpret chords and know what extensions, alterations, and substitutions to play then he or she probably doesn't belong in his band. When I was starting out players would sometimes call chords, and they would say "G....Cm...B7..." and so on, because there wasn't time to say "Gmajor9#11" or whatever. With that in mind here's a link to a helpful site called The Vanilla Book. He used to have all these tunes bundled for download, but he passed away and I don't know what happened to that link. Still, you can see the basic changes to individual tunes by following the links, and you can print them out if needed. Also here's the link to the reason for the book, similar to Chick Corea's reasoning.