Rolling out after or before the leavening process? Assuming that you want to create home made pizza and bread, it's better to create the final shape when you create your dough or after the leavening ?

I think that part of the problem is the fact that the average oven can't generate the same temperatures that the industrial ones are able to produce or the ones specifically designed for the pizza; so I'm thinking that maybe a leavening process after the creation of the shape can possibly give more porous to the final product making it easier to cook thanks to the porous and the air inside them that conducts heat .

Or I should go for creating the shape just after the leavening and use something to revive the product during the final steps just before putting it in the oven ?

I'm using sourdough starter by the way.
In making bread or pizza dough, there is no step called "leavening."

While there is some variation in method, depending on whether a preferment is used, in general, the active culture (whether it is sourdough starter, commercial yeast, or a combination) is added very early in the development of the dough.

The dough is then kneaded to develop gluten structure, and proofed to allow flavor to develop.   This is normally described as allowing it to rest until it is doubled in bulk.  

Then, it is "punched down", deflating most of the rise that happened during the proofing stage, and shaped into its final shape, and possibly placed into a mold or form.  It then rises again to a greater or lesser extent before baking begins.

There is no before or after the leavening.