how do I start my car without the remote

Hello, The hard key will not be used to start the car, the position of the key is what will work when the key battery is dead. In your owners manual, a procedure will be described for this situation. Normally, GM likes to dedicate a little spot in the center console for the key to sit on or plug in, and there may be a place to install the key on the dashboard. Most times there is a backup for smart keys built in, and most times it works.