I'm not going to invite my friend over Friday night because he doesn't play Fortnite.
What does him not playing Fortnite have to do with you not inviting him over?
He wouldn't be interested since I'm going to be playing Fortnite.
That sounds reasonable. You don't have to hang out with your friend if they're not interested in what you're doing.
That's a good point. Maybe I'll do something with him on Saturday.
I think that's a good idea. You should let him know that you want to do something else on Saturday, so you two can hang out then.