Its like how can you heal a wound when the knife is still stuck in you?

I'd start with a nice walk around the neighborhood, work your way up. 15 mins a day then when you are feeling it move up from there. I also think exercise should be fun so I do dance workouts from YouTube, growwithjo is a great channel and she even has seated and workouts as short as 10-25 minutes. Find something you like if its walking, a sport, a yoga class at a nearby gym.