I was driving the other day and. Jeep shut complety off
If you mean that everything is non-functional, as if you switched the ignition off, then there is most likely an electrical issue. If absolutely nothing comes on (lights, radio) when you switch the ignition on, the ignition switch may be the culprit. It’s possible that a connection within the electrical portion of the ignition switch failed or shorted. Another possibility could be a broken or loose battery connection to the starter, or a fusible link near the starter. If you mean the engine shut down and will crank but not restart, there can be a number of causes as well. A failed fuel pump, any number of sensors like the crankshaft position sensor, or even the engine control unit may have failed. Have a certified technician look into the no start condition to find the exact cause.