This question has been asked before and from skimming the thread I’m not sure if there was really a great answer. There was a suggestion for Privacy Guides to create a Samsung hardening guide that seems to have gone nowhere, but it includes some information in the draft. Besides that, people usually just link to this answer for very basic advice. I’ve also seen people recommend Canta.
Because Privacy Guides hasn’t really addressed this well, I usually direct people to The New Oil’s Android mobile settings guide which seems to have mostly good information.