i need help

i just recently bought a 89 regal gran sport i have 2 problems 1 i cant get the reverse lites to work i tryed replaceing them but still i get nothing and 2 the radio is stuck you can switch the options volume to bass am to fm but you cant turn the volume up change the station nothing i was told it could be a code that needs to be entered but i dont know where to enter it or what it could be any help appreciated