These are small narrow bunching onions or scallions that grow and are divided from the base. They are technically perennials that will reproduce from year to year. We grow them in our large 4.5" pots and seed them with 3-4 plants per pot. They can be grown in the ground or in a pot in a clump, or separated and planted into a row for larger onions. These will not bulb like regular onions.
Although these are bunching onions and will not bulb, read more about growing onions
here