I would agree with others and say start with yoga... very gentle flow yoga. Baby steps. Some yoga poses take a great deal of overall body strength and
balance, you don't want to start there. Start at the beginning.
Also - contrary to some belief, get to the gym and do some slow stretching and rolling, also use some 3 LBs dumbbells to do some very basic
strengthening exercises like 5x5's (Yes, I said 3 LB dumbbells) not a bar or anything like that.
You should be drinking a ton of water as well... if you're going to start stretching via yoga or any other means you're going to want to flush toxins
out of your system as they're released.
Yes, I'm a masters licensed nutritionist and sports trainer. PM me for questions or concerns.