How do you ladies diet Breastfeeding and loosing baby weight?

Bl

I want to loose some of the weight but not sure how not to loose my supply? Ive heard u need to at least have 1,800 calories a day? I don’t eat very healthy lol I love cookies and that’s my problem I lost a lot of weight but with that my milk supply was low I brought my calories intake up and gained 8 pounds back to pick up my supply I also notice when I don’t eat enough I don’t get good amount of milk a day and I’m constantly hungry!!