What can be done to minimize the appearance of scar in the belly area? (photos)

At least from the photo, the primary scar issue is hypopigmentation. If that is indeed so, then the use of professional microneedling accompanied by the application of prescription strength pigment promotiing topical medications can help to improve both the texture and the color of the scar. If there are any elevated areas, these can be flattened with the use of intralesional triamcinolone. Make sure to consult with a board certified cosmetic dermatologist. Best of luck.

Dear cauliflowers,
it is hard to tell for sure without an examination. If you are considering surgery, I would suggest you consult a board-certified plastic surgeon. Only after a thorough examination, you will get more information and recommendations.
Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery