@Piyush123 can be both. Yes is weird, Jesus is the son of Maria after being impregnated by the Holy Spirit. Some concepts may vary depending of wich branch of Christianity you ask.
In general God is separated in 3 beings:
"The Father", the father of every one, the classic characterisation of god. "The Son", Jesus who can be interpretated as god incarnated as a human. And "The Holly Spirit", Representated as a fire, light or a White dove, this las one manifested and announced to Maria that will have the son of god.
Those 3 are not the same but thogether are the "Holly Trinty" which is the very concept of "real God" at least in bettween Catholics.
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Btw, About Buddha is a bit hard to explain because is necesary also talk about Hinduism (wich Im not very well versed), but Enlightenment of Buddha means He escaped from reincarnation cycle. Wich maintain our souls to the phisical world making them suffer... Because our souls are the shattered parts of a bigger one wich I believe can be interpretated as God too I guess?.
The point is while Buddha is not a God it self, He is in a God like position because his soul ascend higher a realm. Actually He didn´t wanted to be worshipped by his followers while he was alive, the point of his teachings is that everyone can become "Buddha". More than Jesus comes as a Messiah, Buddha suppost to be like that guy in your class wich has very good grades and try to show you his studying techniques.