C programming - File IO help?

I'm learning File IO in my Intro to C class, and I need help with my lab program. What my lab is supposed to do is to read in a .txt file that contains simple mock bank account information using the fscanf function, and then use fprintf to write to the .txt file after the user has inputted information and stuff. But, I don't know how use fscanf to skip a line and read the next line (for the account number) ...and then the next...until the end of the file. how is fscanf supposed to read the value of the return key?