Semolina flour is a flour made from durum wheat and is used in making pasta. It is high in gluten, available in coarse or fine texture and can also be used to make bread.
You might do what so many of us have done when new here. That is do a "search" for whatever interest you. Second, pick a recipe and make a pizza, make two pizzas, make a bunch of pizzas. Keep good notes on what you did. Then you can start asking questions which might help you. Or, who knows, you might make the perfect pizza on the first try.