Need advice for returning to excercise

Amoc1973

I  have mild-mod LE. Recently had the bypass procedure & seeing results. The swelling has decreased a lot but of course it is not gone. I will prob get the ok to excercise at 6 weeks post op. It's ok for me to walk now at 4, but I would like to get back to running, etc. Prior to cancer & bypass I did crossfit. I'm not sure I'll be able to or should do that type of hardcore excercise again. I'd love to work back up to that but I'm sure this will take a long time. I don't have money for a trainer. I was thinking starting w mat Pilates or maybe yoga. But I don't really know where to start ie what I should & shouldn't do. I've read the recommendations of start low go slow but it's really hard for me to gauge as I was an avid exerciser before (a bit obsessed actually). Maybe  there is yoga for s/p breast ca & LE???? There is an excellent studio by my house. I could use the relaxation aspect of yoga. Any advice from anyone who has 'started all over again' would be great.