For game course, by which I mean the formal ones, it's always 72 storkes.
2. always 18 holes for a full games, there are 9 holes-game to save time which I played regularly, people will mention the 19th hole occasionally, that's the snack bar at the end of the game, or after the game, MEET YOU AT THE 19TH, meaning see you in the bar for a drink
3. Nobody I know plays up to Par, say Hole 1, is 550 yards, it's a 4 stroke hole, to get up to par, you have to play everyday like the pros do, the British Masters game had a final score of 2 above par. In fact, I don't know anybody in my firm who has a single digit handicap, my golf coach is handicapped at 5 above