How far from a sun would a jupiter-sized earth-like planet need to be? (and other questions)?

How massive a rocky planet becomes determines what gases it is able to hold on to to make up it's atmosphere. Once you get to jupiter-sized, the planet is able to hold on to the most abundant gases in the cosmos, hydrogen and helium, so those gases become the main constituent of the atmosphere, as they are in the gas giants. Btw, the gas giants probably have rocky/metallic cores the same as the "terrestrial" planets. We just can't see a surface because the atmosphere is so thick.

So an earth-like, jupiter-sized planet would not arise naturally. Btw, gravity would also be a problem for humans on such a large planet.

The distance of the habitable zone depends on the brightness of the star, and not on properties of the planet.

A terrestrial planet the size of Jupiter is probably impossible. Firstly it's unlikely that there'd be that much rocky material around. More critically, even if there was an unlimited supply of rocky material, as the planet grew its interior would get more and more compressed, so it would get more massive without getting bigger.

Well, you already have kind of an issue... there physically cannot be a planet that size without it becoming a gas giant. All that mass will begin to generate core fusion, thus turning the Jupiter-sized planet into... well, a Jupiter-like planet.