how do u ask someone what food they like.

As for food itself, I remember one of my first words was "tabemono" = "something to eat"

Do you like this food? = Kono tabemono wo osuki desu ka.

Which do you prefer? = Dore gaa suki desu ka.

Which do you like? = Dochiara ga suki desu ka.

OR, without your specific English, I'm not sure any of the above will be exactly what you want.

Sra