The bare minimum that I think you could watch are:1. Iron Man.
3. Captain America.
4. Avengers. (The 2nd one was better, but it is optional.)
5. Guardians of the Galaxy. (The 2nd one was also better, but optional.)
6. Dr. Strange.
7. Black Panther.
And then finally...
8. Avengers Infinity War
9. Captain Marvel.
10. Avengers Endgame.
I didn't like either Ant-Man movie, nor did I think much of the Spiderman movie.