Really important question... Plz help?

Kk so this is my cuzins account u know she left it open on my computer and I need help with a question plz no rude or mean comments I'm 210 lbs and I'm 13 and I'm like 5'4 I really wanna lose like 50 lbs by may does anyone have any good tips like ik I wld need to excersice but does anyone have like a good regimen a 13 year old can follow thanx much