Like what the other mom said this is cradle cap!
My son is 2.5 months. I gently massage in Bzu Bzu baby coconut oil on my baby's scalp 1 hour before shower (be careful not to press on the soft spots on the top and back of head!), then use a silicon brush (you can search cradle cap silicone brush on Shopee) to wash his hair in circular motion. Don't use too much - just about $1 coin or slightly more. No scrubbing and no peeling the skin also - now his cradle cap is mostly gone in about 3-4 weeks, left a few small dry patches and very tiny flakes :)
But even if you don't do anything, it will go away on its own in a few months' time.