Theyre probably a bit big to separate out now, but what about trying cuttings?
Plant this one into a pot about twice the size, and cut all the stems down to just above the third node. Each cutting should be ‘leaf node - stem - leaf node - stem’. Trim off the bottom set of leaves on each cutting, and soak them all in a jar of water, ensuring the bottom cleaned node is submerged. ( You can leave about half an inch of stem below the second node).
In about 2-3 weeks you should have loads of roots springing from each node, and in 6 weeks you should have a few healthy trays of basil plants growing in pots sized in your picture and a never ending supply of basil.
Bonus: all the leaves left after trimming have on slices of mozzarella with a drizzle of balsamic.