How to do workouts when you are not young and might have some injuries

I am 68 and both hips have replacements so rolling live is a little risky and I don't roll with people I do not know and not even with all the who I know.

I like situational sparring and games as an instructor, but looks like I need to go to dead reps and predesign movements. It might not help rolling, but it would be some kind of physical exercises. - and it would get me back to the mat. I have access to the gym so I can go and drill with a friend when ever I feel like it - and friends have free time

Maybe someone has good compinations or flow roll drills?