I have typed a c program how to save that program on repl.it
So, the way repl.it works is that once you click on "New Repl" and you pick the language and then you can optionally fill out a name and description then click Submit. Once you click Submit, a new repl is created. If you didn't name the repl, it may go into your "Unnamed" folder on your "my repls" page.
And any changes you make inside the repl are automatically saved for you. You never have to click on a save option or do any keyboard shortcuts. The repl tracks changes and saves those automatically.
I hope that helped!