No.
That is would be the very definition of a paradox.
He COULD be the father of some of his female friends though.
We'll see what happens as the story unfolds.
His time travel window goes too far on the past though, as it is now he could be Skylar’s dad (and that would explain Luna), but everyone else including himself is a few years too young.
That said, Hoodie said he’d destroy the machine this time, so it’s possible that the next trip goes to a few years later and ties everything up.
Sure it would be a paradox for him to be his own father, but depending on the time travel theory the author subscribes to, that may not make it necessarily impossible. There is a great classic time travel novel with this twist (not going to mention the title as it would be a spoiler).
Can't be Skylar's dad. She states clearly that he's in prison for selling weed. I was thinking the same thing until I remembered that she tells MC that in the park. I think the Luna thing is just that Luna remembers him from the diner and she's scared of him because while people can look very similar, it's impossible for people to look exactly alike (excepting twins) without very extensive plastic surgery. Also, she says she never forgets a face, implying that she might have a photographic memory.
That's a fair point. I had thought of that. It just seems to me that Skylar and MC are close enough that she would have told him that the man in prison isn't her bio dad, and Luna is close enough to Skylar who is an adult and probably would have told her that her "dad" isn't her biological father. Speculating way too much. lol *shrug*