Belly fat loss

So I’ve been having trouble since I was a freshmen with belly fat. I’m skinny but I have a huge belly. I suck in so no one notices but me. I moved in with my mom after living with my dad for 5 years. In that time I was skin and bones because my stepmother starved me to keep me “skinny”. So as soon as I moved in with my mom I had the freedom to eat whatever I want! I loved it but then I started gaining weight in my tummy and nowhere else. I want to feel confident in a bikini this summer. This is what I look like right now. From the side I look ok but from the front I feel ugly. I want to slim down my waist. Also when I sit my rolls hurt my left rib I don’t know why but it hurts a lot. And also my belly button piercing hurts when I sit. I wanna be able to sit down and be comfortable. Please send me some tips on how to slim down my waist. I’ve googled everything and even bought some products blindly not knowing anything about it. Please help! Don’t mind the boob slip