weight i guess idk

okayy, so 2 summers ago i was around 199 pounds, and back then i was only 13, and im a girl around 5’5”. i know that’s like extremely obese and i took care of it and went down to 159 pounds in like 2 months, not by a diet but i was extremely strict with myself and would push myself (i know it’s the worst way to lose weight but it stayed off.) anywho, now i have been eating a lot due to my cycle and just stress, and went back to 180 pounds, now being 14. please don’t say anything mean, im not gonna cry over it i really wanna lose weight again. but is there anyway i could lose 20 pounds easily? last time i did long workouts, and was terrified to even go over 500 calories for a DAY. i know it’s unhealthy but i don’t know what to do.