How long after........?!

I'd wait 2 months before doing abdominal exercises or weight lifting. But of course ask the doctor. I had 4 major abdominal surgeries on my reproductive system over the years, each time removing various parts of it through a 7 inche vertical abdominal scar that sounds like yours. With the first, I resumed normal activities really quickly. And I ended up getting a lot of adhesions, which are internal scar tissue that can be painful. The adhesions may stretch between various internal organs and the abdominal wall, and then when you bend certain ways, it could hurt. Potentially. Or you may have no problems at all. In any case, after my next 3 surgeries, I was sure to take it easy for 2 months. My doc said I shouldn't lift more than 5 pounds for 2 months. I did do things like walk for as long as I felt fine and didn't strain myself. So that enabled me to do a bit of aerobic activity. The thing I was really cautious about was putting stress on my abdominal muscles, until I was sure they were healed. And I had no more problems with adhesions with the subsequent 3 surgeries. There's always time to rebuild the strength in those muscles later. But once you have damaged them or caused adhesions to grow, you can't go backwards. The uterus anchors a lot of mucles so you need awhile to heal those muscles.

Ask the Dr. They will be able to give you the approximate schedule for you to work out.
Please ask the dr. that did the procedure!