Try doing more research about theriathropy, and I suggest finding out your theriotype(s) before coming out, so then you can most likely answer any questions your parents may have.
You could try and write a letter about theriathropy to give to you parents. You could also (if you’re allowed to) put a therian flag on your door. (This is how I come out as a therian)
You could also do quads (if you do them, not all therians do quads) around the house, in front of you parents, in your yard. (if you have a yard) ;) basically anywhere. I do tho suggest doing quads ether on a carpet or in the grass, because it can hurt you hands if you do them on hard surfaces.
You could also try making gear (again not all therians do quads are wear gear) and you could maybe wear those around the house or in front of you family.
I hope this helps. :D
