So no Biopics or 'based on true stories'

I'm doing a case study on how a lot of movies characters are actually inspired by real life people rather than just made up out of thin air

Norman Bates in "Psycho" is based on Ed Gein, who apparently was partial inspiration behind Texas Chainsaw massacre and Silence of the lambs

Kayser Soze was inspired by John List, a man who killed his whole family and started a new life.
Also uproxx.com/filmdrunk/nightcrawling-is-a-real-thing-meet-the-guys-who-inspired-jake-gyllenhaals-creepiest-character

Frank Costello - 'Whitey' Bulger

Rocky Balboa - Chuck Wepner

Joker - Conrad Veidt

Indiana Jones - Hiram Bingham III

What do you think of stuff like Girls, Insecure, Funny People, The King of Staten Island, Workaholics?

All of the main characters have different names, and slightly different lives, but they're clearly just the creators playing themselves.

But some good examples of what you're looking for

Van Wilder- based on comedian Bert Kreischer

The Dude (from The Big Lebowski)- based on Peter Exline, some guy that the Coen Brothers knew

I think it’s dope and the easiest s*** to create. Write what you know.

The Master and L. Ron Hubbard

Michael Cera’s character in Molly’s Game is famously based on Tobey Maguire

The Farewell with Awkafina I think was basically Lulu Wang’s experience that she wrote and directed

White Hunter. Black Heart - John Huston
Dead Ringers - Stewart and Cyril Marcus
Fitzcarraldo - Carlos Fitzcarrald

If you're allowed to do TV, The Wire is full of these