First, preheat the oven to 450°F.
Using a mortar and pestle, crush the fennel seeds and then pulverize them in a coffee grinder, or place them into a plastic bag and crush them with a rolling pin as fine as you can.
Mix together the ground pork, fennel, garlic, oregano, basil, salt, and pepper in a medium-sized mixing bowl.
Add the sausage to a skillet over medium-high heat and break the sausage up into crumbles, stirring occasionally and cooking until there is no pink left and it is lightly seared. This may take about 8-10 minutes.
Drain the sausage on a paper-towel-lined plate until you are ready to assemble the Sheet Pan Pizza.
Brush olive oil over a rimmed 9x13-inch baking sheet.
Roll out the pizza dough and stretch it out to fill the whole sheet pan in as even a layer as possible.
Spread the pizza sauce all over the dough, leaving about ½ inch border around the edges, and top with half of the mozzarella cheese.
Add the crumbled cooked sausage to the cheese layer before adding the remaining mozzarella.
Sprinkle the cheese layer with oregano and garlic and bake for 15-18 minutes, or until the crust along the edge is golden brown and the cheese is melted and appears golden brown as well.
Remove from the oven and let the pizza cool for 5 minutes before slicing and serving with grated parmesan for topping, if desired.