Need to know how to change a gas pedal

You wouldn't go to the yard with no tool box or just one wrench. You have the perfect opportunity to answer your own question by looking at the donor car. Also look at yours to see if there's any indication the pedal was bolted to the floor. If it was, the lever hanging down won't have any holes or attaching points on it. Many pedals do not bolt to the floor. Instead, they pivot on the end of the lever. Most likely you'll need a pliers to pull a retaining pin to get that type off.