Can I use store-bought flour instead of freshly milled?

Yes. If you don't have a grain mill at home, you can use whole wheat pastry flour (U.S.), or any regular whole wheat flour (Europe) instead of fresh-milled soft wheat flour.

Do I need a special loaf pan for this?

No. A bread loaf pan with tall sides makes a neater slice, but a regular bread loaf pan works just fine.

Can I make this without a stand mixer?

Yes. The dough will be sticky, but you can do the initial kneading by hand, followed by three rounds of stretch and folds.

Do I need to shape the dough in four sections?

No. Shaping in sections makes the loaf rise evenly. It's easier to make sandwiches if slices are the same size, but it's totally optional. You can also shape one long loaf instead.

Can I skip kneading and just do stretch and folds instead?

No. Fresh-milled bread doughs always benefit from a good, initial knead. It helps oxidize the dough, and build gluten early. In addition to the bran, fresh flour contains active enzymes that break down gluten and interfere with gluten formation. Kneading early ensures a dough that remains strong throughout bulk fermentation.