If you want to tame a rhino make sure the area is clear if it's not clear kill the direwolfs or other wild dinosaur and stay up hill so Rhino can't get you and use Shocking Tranquilizer Dart it takes to 3 shots and hes or she down.
I play Xbox official prim+ pve. I have found that required amounts of taming food are spot on, the amount of narcotics the app suggests is quite low for my needs. Be wary of this. I find it safer to first quadruple the amount suggested ans then add a stack to keep torpor above half. Just saying.