Marvel is one of the biggest movies company in the world. Which one of their movies would be your best they have every produced? It would be Avengers for me and also Iron Man.
I really enjoyed The Black Panther. It's my favourite Marvel movies and it did so well in the Box Office. The recent Black Panther : Wakanda Forever wasn't any good compared to the first movie.
For me, it's Doctor Strange in the MultiVerse of Madness that would be by best movie produced by Marvel's movies industry. I watched The Black Widow which is good but not in the same level with Doctor Strange in the MultiVerse of Madness.