Does Blue Cross Shield cover belly fat removal and skin tightening?

Hi, thanks for your questions. What you are describing is considered cosmetic surgery by insurance companies, and therefore not covered. There can be confusion because in some circumstances an operation called a "panniculectomy" is covered by insurance. Typically, approval of this requires significant overhanging skin after major weight loss (100 lbs or more), and difficulties caused by the overhanging skin such as recurrent bacterial infections. A cosmetic tummy tuck should NOT be considered weight loss surgery.
On the other hand, actual bariatric weight loss surgery such as gastric bypass, gastric sleeve, or lap band may be covered by insurance. These are typically covered if you are very obese, or obese and have medical problems caused by obesity (such as diabetes). Checking in with your primary care doctor is a good way to get started if this is a route you'd like to pursue.

Cosmetic surgery is not covered by health insurance. Only surgery which is reconstructive in nature is considered for coverage  by the insurance companies. Good luck!