I think I see where you're going with this. I could be wrong, of course.
Here's a possible workflow:
1. mix your bagel dough, let proof, whatever the recipe calls for
2. roll it out to a 1/4" thickness, diameter sized to fit your skillet
3. heat up your skillet, place the dough and add already boiling water. Boil at low until the dough floats.
4. drain the skillet, saving the hot water for the next dough if applicable, and put the dough on a screen
5. In your preheated oven, bake the dough on the screen until it is browned top and bottom
6. at this point you can save the cooked dough, freeze, fridge, whatever, until you are ready for the final step
7. top the dough as you like and bake at 425 just long enough to bubble the cheese
Then enjoy your bagel pizza!
I find this interesting - I love bagels, and I want to see pictures of the finished pie. It's basically the same concept as using croissant dough for a pizza base: another way to enjoy the world's greatest food!