In PUBG while it can be fun, it heavily relies on RNG especially in the first few minutes of a match. If you don't get a gun within that time, it's pretty much over or you camp somewhere for a long time and hopefully somebody dies near you or something.
In Fortnite, you can break a building and collect materials to help you survive if you have no guns in the first few minutes. Also the building aspect makes the game really hard at times especially in squads, building forts under constant fire is fun. The item pick ups aren't as in depth as PUBG though, there's no stocks, extended mags, silencers(but there are weapons that drop that have the silencer already attached) and a few more things. Sadly it still has one map that appears to change whenever Epic games decides it should change.
Fortnite also has extra game modes sometimes like Just Explosives, Just Snipers, 20v20v20v20v20, 50v50, a few others I can't name. Oh and there was one where there was extra loot and materials everywhere and the chances of better guns dropping increased.
I played the 20v20v20v20v20 and it was serious fun when the entire team stuck together and built forts together and ate through small towns like locusts on crops.
My Epic Account is ImpossibleGore if someone wants to play sometime.