brake light and turn signal not working

brake light and turn signal not working Same issue . Driver's side tail light brake light and turn signal not working . Passenger side is working no reverse lights that I know of . Bulbs seem good fuses seem good. I'm not sure where under the hood the relay Could be. My trucks been fiddled with here there and everywhere fro. Old owner . Help please?! -katelyn 1988 Chev suburban some wires under dash are dangling I'm not sure where to Start without having a multimeter