Hmmmm...really hard to say. BUT, one concern I'd have right away bc they're puppies, and it's on his head - is ringworm. In dogs, ringworm doesn't always (or even often) form a ring - it can just look like a bump, a red spot, a blotchy area...usually starting on their head.
It could be nothing, but if you suspect ringworm in the least - get to the vet asap bc you don't want it spreading!
And, WELCOME TO YT
!