https://www.tckpublishing.com/how-to-write-a-protagonist/
https://www.masterclass.com/articles/writing-101-protagonist-vs-antagonist-chara...

So, one of the best things I learned about protagonists is this is the character who hurts the most. This is the one we want to root for and we want to see grow and change at the end of the story. It doesn't always happen. The choices that our main character or protagonist makes can be difficult or unpopular or even wildly bad for their futures - but the choices are theirs (ours as writers).

Give that protagonist life of their own. Over the course of this prep and your drafting of the novel let them become a person you know so well that they can only make one decision and have it be the right one for them, even if you wouldn't do it if your life depended on it. That's the mark of a great character.

Good luck everyone!!