so i switched to piccolo for the first time a month ago
and then i tried to play the flute
but it was really hard and i can only make a sound for B-flat and C
so now im dont know wahat to do DD:

A. Practice.
B. Get a private teacher

you need to practice!, you need to get used to switching betwen them .

True. It takes me about five minutes to dial in my tone after switching from clarinet to flute. But it took me hours at first.

Don't give up This is absolutely a solvable problem if you work at it.

Remember to relax your lips, you may have tightened up to play the piccolo, and if you're too tense you won't get a good sound. The embouchure is different, so you have to let your lips adjust for it. Try with a mirror to see what you're doing. Try playing flute first, then picc, then back to flute.

(If you think that's hard - try switching between flute and oboe!)