There is not a Par 6 in any PGA licensed golf course.
Par 5 is the longest hole for a golf course.
To get under par.
A par 3 on a golf course in more than 5 yards but less than 650 yards
Depending on the golf course, the set par can be anything, but it is very common for the par to be 3 and 4
It means that you shot par for the course.
A standard golf course is made of 18 holes, these holes have pars. A par is the set amount of strokes the hole should be completed. There are par 3, par 4 and par 5 holes, the 18 holes are totalled and that is the par of the course, it usually totals 69-73.
The course designer, it depends on length really.
It is called an albatross.
An executive golf course is shorter and is rated as an easier course according to par. An executive course is designed for inexperienced players, or golfers who are short on time. It is characterized by mostly par 3 holes. There may be one or two par fours, and a rare par 5.
That means that the par for the course is 71. And THAT means that if you get par on every hole it will equal 71.