I played d4 a while when it first came out but I recently came back to check out this newest season. What's the preferred method for leveling? I'm currently level 56 and in nightmare I guess? I'm trying to reach the point I can find some items to sell, and everything I see for sale is level 80. Is that the highest actual level an item will require? Is there a way to get to that level without it taking weeks of grinding?

Item level doesn't matter, only item power does (925 is max now)
Just blast dommhaine tunnels over and over to level up to level quickly

Gotcha, so keep grinding until stuff starts being 925. Got it. Thank you.

you also need to be in tier 4, not 3

925 items drop from duriel and world boss they are not common anywhere else fyi