How do I seriously lose weight?

I was a swimmer and I swam 6 days a week for 2 hours. I don’t have time anymore bc I work and I’ve been feel terrible and down lately because it seems like I have an actual baby growing in me. I feel I look ugly all the time and I have no motivation. Is there any small tips you guys have to help me get started? I’m a a vegetarian, 5’4, 190lb