Gonna try and lose 20 kg in 3 months

Hello folks, first off sorry if i write something wrong because im not that good on speaking english.

So... yeah it all began 2-3 years ago when i started somehow gaining weight..strange part of it is that i can't remember how i gained so much weight, currently i have 70 kg (154 lbs) and yes before that i had only 50 kg (110 lbs).Since summer is coming, i decided ill dedicate all of my time to work hard and lose weight! The only reason im doing this is because i still like one girl  that i felt in love since i had about 11-12 years, and for these past years i still can't forget her.My second reason is because of my passion or so to say football.I've started playing football when i was only 6 years, but i stopped 2 years ago because of my weight...it's really sad for me and its really the most important thing for me.I've got offered to play somewhere in England, but i couldn't because i had some personal problems back then.So yes, i've been bullied since i've gained weight and called by mean words but hey thats the world you know, i moved on and i really don't care what other people think about me..Alright so the summer is coming i'll have 3 months on to work and lose 20 kg to go back at 50 kg which is kinda good for me, im 15.I'll ask you guys if you can help me throughout these 3 months with what kinda stuff CAN i eat, and what i can't eat, what should i do everysingle day of those 3 months and stuff like that.I don't really want to have 6pack or whatever, i just want to be a normal person, so i dont really need hard training for my muscles, just to lose small ammount of weight in these 3 months.I'm gonna start exactly on 10th of June, and by the time goes ill be listening what you say in the comments and see what i can do! And yes, do you think that 20kg is alot to lose in just 3 months? Oh and also my height is 1m 64cm! I've seen alot of people losing weight almost impossible, but i've decided with the help of some of you guys i will make my dream come true!