You're at an increased risk for hernia after abdominal surgery and while you have an ileostomy. Jogging requires a surprising amount of core strength to stabilize your body as you move through space. Sit ups should be avoided while you still have your ileostomy as they're most likely to cause a hernia. Planks are a good alternative and you can adjust the difficulty by holding them for more/less time.
If you're starting out quite unfit AND you've had surgeries AND you still have your ileostomy, I would start with going out for a brisk walk each day, preferably over varied terrain (uphill/downhill etc). Work your way up to an hourlong brisk walk, and then start alternating jogging and walking. You can decrease the amount of walking and increase the amount of running over time... but I suspect you'll be having your takedown already by then
Just out of curiosity, may I ask why your surgeries have been spaced out so much? I'm guessing your first surgery was emergent?