M.W.
Just keep giving breastmilk! No need to introduce regular milk. God made breastmilk perfect! It changes as your baby grows so it contains everything your baby needs.
I breastfed our son to 18 months. He had only a few sips of regular milk out of my cup when he wanted before that time. I did NOT serve him regular milk, just breastmilk till we completely weaned.
Congrats on giving your baby breastmilk this long!