i want to lose fat but not muscles

i am 16 yrs old i got some fat so i do cardio, cycle and ball in my home gym for losing fat i have losed 3 kg in 20 days by heavy exercise i have muscles too but i think while losing fat am i losing my muscles too plz tell i do cycle for 55 min and lose 500 c and cardio for 12 min and lose 100 cl and ball exercise 300 times and do gym in evening too but less only 250 cal at evening please tell and what to do for not losing my muscle i am not doing exercises for building body as people say one should do after 18 yrs i am doing only now for losing fat i had reached 80.2 kg then in 20 days of execise i am 77 .2 i will lose some more weight but not wanted to lose muscles which i have plz tell am i doing right how to the proper workout