I can see where you’re coming from, but this is the start - identifying that it’s foolish to care about what other people think about your body, especially people you don’t know or care about. Do you think you look good in that outfit? Then why care what the people at the store / party / etc. think?

You can choose to work on improving your body through diet and fitness, but do it for yourself - If you do it for others, you will never be happy because there’s always someone out there who will tear you down, who is prettier, you will likely always have a bit of cellulite, flaws, etc.

I don’t want to make it sound like it’s easy (it’s not), but you have to start somewhere, and a mindset change is a good place to start.