"In any good novel, a writer creates fictional characters by giving them goals, throwing obstacles in their way, and creating conflict. Writers connect a reader to a story by making characters relatable. Character development is one of the literary terms writers hear a lot, but it’s an essential element of fiction writing, and a hook into the narrative arc of a story."
This is a fantastic read on developing characters in your story. Character development can sometimes be tough and this short read of 8 crucial tips gives fruitful advice to help make your characters strong.
https://www.masterclass.com/articles/how-to-develop-fictional-characters