so i just played through ff7 for the first time and there is something i dont get

sephiroth is supposed to be clouds father?

and jenovas his mother?

SPOILER ALERT AHEAD

Ah, that's not actually correct Misty. Cloud's parentage was shown during the Nibelheim flashback scene in Kalm during disc 1 (but only if you decide to enter Cloud's house during this scene - it's missed otherwise) - his mother's name is never mentioned but she is shown living in Nibelheim during the Nibelheim incident only to to perish when Sephiroth destroys the town.

Cloud's father though is never actually shown in game, Cloud only mentioned during that scene that his father died "when he was very young", so it's likely Cloud never knew him. That's all that's mentioned or shown in the game about Cloud's parents - Crisis Core doesn't really give any extra info on the subject either, despite retelling the Nibelheim incident from Zack's persepective.

But the main thing is Sephiroth and Jenova aren't his parents.

Correct Enkidoh.
Sephy is the son of Hojo and Lucrecia. Jenova cells were used to change sephiroth in the womb, and hence, Jenova is called "Mother" quite a lot. Vincent never got over his love of Lucrecia, and so Hojo experimented on him. This is why Vincent "Slept" for a long time, and also explains the basement puzzle.

Someone is trying to wind you up. :)