Any advice about an abdominal/thigh workout for a teenager?

Im a 16 year old vegetarian who is slim but i want to lose fat and get toned so I can have a body I’m proud of by the summer. I have found arm workouts that I like but I need to find workouts for my stomach and thighs. I’m open to anything.
I would appreciate a workout that burns fat as easily as possible. thank you!