That question is very subjective, i don’t know what exactly you don’t know to use, so please elaborate it more. There is almost a world to learn 
I suggest you to keep trying and ask for help where you get stuck, that is a natural way to learn. For examp,e if you are referencing to nodes, your first need to understand what each input/output does, to don’t connect it wrong (i.e. don’t connect a float (white) output in a vector (purple) input). Or connect them wrong and go by trial and error (a great learning process).