Need to lose weight by April(help me!!!)

Itzz

Okay, so I'm 242 pounds(size 16-18) and I need to drop down to a size 14-12 so I can get a beautiful dress for my boyfriends prom. I workout 3-4 times a week but I don't know how to eat or what kind of diet to lose the weight so please help.

(Picture of me rn and picture of the dress I want)

)