I wanted to ask about rules of aqeeqah if it is for a boy or a girl. Is it necessary that for a boy, there must be 2 lambs and for a female, one is fine? Or even one is sufficient for a male too?

There is one narration that says that, but the chain is weak, and other narrations say it’s the same for a boy and girl. Hence scholars do not differentiate between them. It’s one lamb (or another sacrificial animal) for both. Of course the more the better.