what do you mean alphega? so they can bear a child?isn't it?

Did you read the epilogue?

It’s intersex traits. Just like real life where a person has both female and male reproductive organs.
Alphega, is someone who has both alpha and omega traits. Of course they can get pregnant if they have a high percentage of their omega traits. MC only has 1% of omega trait which is why no one know about him being Alphega except for his mom, Haeil, and another omega(mentioned in ch8)and his chance of getting pregnant is very low. But that doesn’t mean he can’t get pregnant. That’s why you don’t look down on that 1%, haha

I have seen a bunch of people comparing this to intersex characteristics/people, but it's a really broad term that rarely has both reproductive systems working, sometimes it's either XX or XY that work but also have ambiguous external appearances(having a working uterus but a penis[which doesn't mean that the person will produce sperm]) or another case(having a vulva, but no uterus, maybe an undeveloped scrotum). Intersex is not rare, but rarely talked about and therefore poorly understood. There are cases where both systems work, but that's just one or so of MANY other dispositions under the term Intersex.