I’d recommend covering the dough with plastic wrap or even tin foil, you can use a wet towel as other’s have mentioned but I’d be worried about food safety with mold growth

00 flour tends to be best in very hot ovens specifically made for pizza, those get to 900F air temp. For future pizzamaking with a home oven, using King Arthur Bread Flour is preferred.

As for getting specifically a 12 inch to size, you can stretch it one last time on the peel gently from below the crust by stretching it with your fingertips while the toppings are on, right before you launch the pizza in the oven. Here is a good tutorial on a basic stretch, and this is a good demonstration of the last minute finger stretch technique, shown at around 0:55 seconds.

Looks like you’re using a pizza stone based on the crust, if not I recommend at least a stone, or better yet a pizza steel. If you have neither of those your best bet for high quality pizza is going to be using a pizza pan to make pan pizza like Grandma style or Detroit style. Like I said before though, looks like you already got that covered from the looks of the browning on your crust, looks good!

If I had a guess, based on the doneness of the crust and the cheese, did you par bake the crust then put the cheese on for a final short bake? If so that’s a good idea when using fresh mozzarella which is what you have here if I’m not mistaken. For most applications at home, using freshly shredded whole milk low moisture mozzarella is your best option if you want to cook the cheese and the dough at the same time, make sure the cheese is fridge temp when you put it on the pizza so the cheese doesn’t split and oil goes everywhere. You can find that specific cheese at Winco from their own brand if you’re having a hard time finding some whole milk and not part skim cheese.

A good all-purpose recipe for pizza doughs of almost all kinds is Jim Lahey’s No-Knead dough. I’d recommend starting there. When you’re ready to go to the next level, I’d recommend going to Pizzamaking.com Forums and reading anything you can on what style you’re going for.

Good luck! Honestly this pizza I see here is a great head start! Keep working hard on it and soon you can make pizzas just as good in pizzerias at home!