hi and welcome to the forum! :)
the best and probably the fastest way is likely by using subway line 2 to the central station. from there, you can go by suburban train or streetcar. a one-way ticket for this distance will cost about 1,90 euro, so it should be affordable for you.
i'm not living in nuremberg, maybe an inhabitant will be able to give you some more detailed information ;)
may i ask where you're from? :)