A knight's page would be addressed as a page. It is important to remember that a page is a servant to the knight and as such deserved to be addressed as any other servant sometimes by name but ussually by title. Heather Ledger in A Knight's Tale starts out as a page and later impersonates a knight.
Knights' pages were typically referred to as "squires." Squires-in-training assisted knights with various tasks and learned the skills needed to become a knight themselves one day.
At first they were pages and then squires.
The Winter Knights has 384 pages.
They did the odd jobs for knights and were in training to become knights. They were the son's of nobles who showed promise of knighthood.
A group of knights is called a "brotherhood" or an "order."
Knights of the round table.
Pages acted as personal servants to knights and barons.
a squire is basically a knight in training, knights start as paiges (pages not certain) who were basically servants to the knights, later they became squires; usually helping knights with their gear (armor, weapons, assissting in battle), and eventually became knights
Pieces of land given to knights as payment were called fiefs.
Some knights were called sirs as they were knighted by a king/Queen for different reasons.
The code of conduct for knights is called a Chivalry.
Pages usually began their training at about age seven or eight. They served as pages for seven years, typically. After that they spent seven years or so as squires, and then they became knights.
You might be thinking of Pretear. There are these knights called Leafe Knights or something, and they fight against these things called larvae that start out looking like seeds.