To cook something in hot oil or butter. Also, baby fish are called fry.
Frying food can make it taste very good, but it can also be unhealthy if you do it too much.
Examples:
I will fry some eggs for breakfast.
The chef will fry the chicken in the pan.
The fish fry is very small and cute.
Don't fry the eggs too much, or they will be too hard!
I can fry a whole cow in this big pan!
The fry swam in the water and played together.