Welcome to BYC - so glad you've joined us.
For a good gender assessment (granted 3 weeks is still a bit early) you really need nice, clear photos that show the whole bird (meaning not being held) in a natural, standing position and taken from the side as there are characteristics that can be seen from that angle that factor into gender. I will say that the comb is flesh colored (pinking would indicate cockerel - though that can still develop in the next few weeks) and there is no discernible wattle development (cockerels develop comb and wattle size and color ealier than pullets)