@Mogima Depends on the author really. From the novels I've read so far on the Metropolis/Urban genre, it seems to usually introduce a cultivation aspect and tends to either blend the two together, aka cultivator in the city becoming OP to ascend or something, or it's a slice of life sort of story. The latter rarely happens. For most of these novels though, you'll find that the majority of the story happens within the realm of Earth (cities), and the upper realm part of the story is pretty much the end arc.
So to answer your question, yes, the story will usually be limited to the city, but don't be surprised when the MC goes to a trek in the mountains or something.
As for your first question, the end goal in most of these stories either is to get revenge on xyz upper realm cultivator that killed MC or to ascend to the higher realm. More often than not, one of these 2 scenarios occur, though other endings like staying on Earth with a harem or something else isn't unseen of.