Uhhh wth happened???

I open this game after a year of inactivity. I'm a bit confused with the new interface and all, but the really confusing this is that I can't change weapon? I know they became skins, but how do I change element? How can I change to fire ice and things like that?

I open this game after a year of inactivity. I'm a bit confused with the new interface and all, but the really confusing this is that I can't change weapon? I know they became skins, but how do I change element? How can I change to fire ice and things like that?