Biggest bang for your buck, calorie intake wise???

I have 1,200 calories to work with per day. Help me spend them in the best way possible.

I need foods that keep you full longer, cut cravings, and boost your metabolism... speed up weight loss. I think this is people’s biggest problem... they know what what healthy food is but they need to be told what to eat and when. Any fitness gurus on here ??? Please and thank you!