When you first loaded the replit starter, you accidentally specified for the run command to be the README.md file. Basically, you did not follow the instructions:
Start by importing the project on Replit.
Next, you will see a .replit window.
Select Use run command and click the Done button.
The last part is what you did not do. The easiest fix is to copy your code into a new starter template and make sure you do that last instruction.
Instead of starting a whole new replit, you can simply:
-in the file pane on the left, to the right of the new file & new folder buttons, click the vertical … button to show more options, choose ‘show hidden files’
-now edit the .replit file’s first line to:
run = “python3 main.py”
yours probably instead says the following if you accidentally clicked the wrong one at the start: