Teenagers who lost fat quickly how? please help! also some tips too!

So thing is by April i want to get to 80kgs i currently weigh 100.2kgs, I am vegetarian so less protein sources (please dont talk about non vegetarian being best yeah man i cant switch to a non vegetarian diet so lets not focus on that )

fyi i was 110 but lost 10kgs in 10 days in december but left my weight loss journey now again i wanna start and i wanna know if its possible to reach 80kgs by 1st of april also whenever i start a diet my mind always thinks about, what to eat next, when to eat next, how to cook it, and what not, so my focus 24*7 is on diet, how do i change it, like i always think about food, macros, etc

also how to resist hunger and cravings

at last wanted to ask is it possible for me to lose 20kgs by 1st of april

and give me some advices, tricks and cheatcode so it helps not only me but people reading the comments.