Can PS4 players meet PC players in online games?

Everyone is always saying that with mouse and keyboard on the PC better Fortnite etc. Can play, which may also be true, but it is still when you gamble on the PS4 with the same conditions for the players? Can PC players also hit PS4 players? If that is not the case, I do not understand all the discussions.

I asked that question because I can't decide between buying a PS4 or a gaming PC.

If you're playing on the PS4, you're just coming to a PS4 lobby, so you can't play against PC players that's the same with PC and Xbox. The only exception is if you're playing at Fortnite crossplay, so if you play with a PS4 and your friend with a PC, for example, you're in a PC lobby