Hey! I know I'm answering this a good ten hours after you posted but I couldn't ignore this since you remind me of a younger me in a lot of way.
Body confidence isn't about changing your body. You absolutely can change with diet and exercise and all of that stuff but the body confidence isn't going to come automatically from that. You still have to learn to love the body you have because a skinnier you isn't necessarily going to look the exact way you imagine. I spent a really long time hating my body, and I mean HATING it. Even when I was at my thinnest I hated my body and therefore hated myself, and it spilled over into how I thought about myself as a person. I used to have a notebook where I would write all of the things about my body that I found disgusting and especially when I was drunk I would write incredibly hurtful things. I developed an eating disorder that still has some health repercussions for me today. Then I started a job where I had to do intense physical activity all day. I started appreciating my body for what it could do physically rather than for what it looked like. The more weight I could carry, the more holes I could dig, the more km I could hike all made me start being proud of my body. That was the change for me, recognizing my body as a machine for doing the things that made me happy. No man has ever been disappointed when I took my clothes off because he knew what he was getting himself into and he was already attracted to me. The only person who was disappointed was me, and that really fucked up my thinking. I'm only about in inch taller than you and maybe 10-15 lbs lighter than you but I am beautiful and I am sexy exactly the way I am. I'm beautiful and sexy when I'm 10 lbs lighter and when I'm 10lbs heavier and even though other people's opinions about how beautiful and sexy I am may fluctuate like my weight, I know that I love my body (even when it's hard to do). Learn to love your body and your curves for what they represent (femininity, strength, comfort whatever) because you're much harder on your physical appearance than most other people will be.
Ignore the comments on here that try to have you reevaluate how "big" you are. They are mostly coming from people who don't understand how different people can hold weight differently. Focus on picking out things about your body that you love and working on the things that you might want to change. But body positivity comes from a change in your perspective not necessarily a change in your weight.
Please feel free to PM me if you want to talk!