Training began when a boy was 8 or 9. When he turned 15 he went to a castle of a friend or relative to begin formal training as a page. At 18 he became a squire and at 21 became a knight.
The knights were fuedal lords that owned land. They would have fuedal relationships with vassals under them. The would give the vassals land in return for service.Usually army service but sometimes...
For the most part, girls were not allowed to be knights. I can think of one exception, Joan of Arc, a young french girl who fought wars, was burned at the stake, and became a saint.
Kights were from...