Step 1. Check the main breaker in your power control box. Cycle it off then on. If no power go to next step.
Step 2. Check the breaker in the power pole. Cycle if off then on. If no power go to next step.
Step 3. Shut off the power pole breaker and disconnect the power cord from both the pole and RV. Inspect the plug ends for obvious signs of burning. If burnt DON’T attempt to use that cord, it is trash. If it looks ok then you should break out your trusty multi meter and start checking for power at the pole then the cord, etc. If you don’t have or are uncomfortable with a multi meter seek help from fellow campers.