How can I be really skinny like Bella Thorne?

Bella Thorne is my absolute disney channel idle! lol. I am 13 years old just like her, same height(5'3), and everything. So my stomach is really fat looking. My mother is okay with me trying to be healthier and things so no worries! lol. I don't wanna be around all summer doing boring old sit ups and push ups! lol. I want a fun way to lose the weight. I love to swim,dance,sing,act,and jump on the trampoline. I have all that stuff I even have just dance 1 and 2. So can you please help me with trying to get a rib showing flat pretty stomach, thighs, legs, and arms.I also do not wanna hear: "Stop trying to be like her, she is unhealthy!" She is healthy and I can if i want to! lol. So please help me!