Raise the plans and you are building on your feet — over the shoulder, the cursor aiming, about fourteen metres of reach. That is the right tool for setting a thing down beside you and, more importantly, for building upward: aiming at a wall’s top face stacks the next course onto it, which is how a second storey happens at all.
Press V, or the View button on the build bar, and the camera lifts off. Your character stays where they were standing; the camera flies with the same keys that walk them, turns with a right-drag, and rises and falls on the wheel. The cursor goes on aiming exactly as before. That is the right tool for laying out a farm, where walking every corner is the slow way round.
On a phone or tablet the overhead view is what opens first, because steering a character with one thumb while aiming with the other is the hard way to lay anything out. Both views are there on either device.