Ms. Marvel is, in my opinion, the best new comic book character in at least the last decade. Her story is unique, inspiring, hilarious, filled with genuine emotion. There's no book I recommend more highly, especially for new readers.
The story of Ms Marvel, Kamala Khan, began in 2014. You should be able to go in fresh, but there is a little backstory I like to tell people: There was an alien hero named Mar-Vell who went by the hero name Captain Marvel. His powers were transferred to an Air-Force Major Carol Danvers, who became a hero under the name Ms. Marvel. Long after Mar-Vell's death, Carol Danvers took up the title Captain Marvel ( Where to start reading Captain Marvel ), leaving her old title Ms. Marvel unused. That is where this story begins.
All-New All-Different Avengers begins at the same time as Marvel Vol. 5: Super Famous. The stories here are completely independent of Ms. Marvel, but are no doubt a major part of the character, so feel free to read them or ignore them: