You either have non-stick pan, then your problem is solve. Alternatively a black iron wok that is well seasoned and oiled has less problem with sticking. The reason is there is a layer of oil between the fish and the metal.
Fish stick to pan when there is nothing in between the fish and the pan when it is being cooked. So in general, it is important the oil is very hot (with some light fumes coming out), and you put the fish down slowly. This will ensure the fish surface contact the oil first and sufficiently to have the outer layer coated before it touches the pan. This will prevent the fish from sticking on the pan. Leave it frying with low flame till fish is almost cooked before flipping over. This ensures the side that is being cooked has “crust” that prevents the meat from falling apart when you flip.