Boy lots of stuff going on here. First the official definition of the "Nearest Point of Relief".
The “nearest point of relief” is the reference point for taking relief without penalty from interference by an immovable obstruction (Rule 24-2), an abnormal ground condition (Rule 25-1) or a wrong putting green (Rule 25-3).
It is the point on the course nearest to where the ball lies:
(i) that is not nearer the hole, and
(ii) where, if the ball were so positioned, no interference by the condition from which relief is sought would exist for the stroke the player would have made from the original position if the condition were not there.
Note: In order to determine the nearest point of relief accurately, the player should use the club with which he would have made his next stroke if the condition were not there to simulate the address position, direction of play and swing for such a stroke.
The NPR is usually within a foot or two of the interference, depends on where the interference is in relationship to the direction you are trying to play your stroke. Most often when you drop within 1 club length from the NPR and as stated the ball can role up to 2 club lengths where it first hit the course..........so your looking at a max of around 3 club lengths from the interference, although it could be a little more.
There are instances where you can drop farther than one club length from the NPR, however it's with a one stroke penalty. Two examples are taking relief from an immovable obstruction or abnormal ground condition in a bunker and you have to drop outside the bunker. You keep the NPR between you and the pin, and you may drop on an extension of that line as far back as you want. (Similar to a water hazard)
Lateral hazards to not use a NPR. With a lateral, one option is to drop within two club lengths from the margin of the hazard. No NPR is involved. As mentioned when dropping from a hazard, only the ball must remain outside the hazard for relief, doesn't matter about your feet. A side not on this is when hazards are marked for tournaments, the committee must take in consideration both left and right handed golfers. They don't want a situation where a player would drop from a hazard and still have to stand in the water.
As far as where you have to stand when dropping, doesn't matter. You can stand anywhere and face in any direction. It just has to hit the course in the proper place and not roll into a position that would require a re drop. There are actually seven things that require a re drop and are listed in rule 20-2c .
I should also mention that when taking relief from an immovable obstruction or abnormal ground condition on the green, you place the ball, not drop, within one club length from the NPR.