Video: The Legend of King Arthur
Use link #1 as your starting point for your research.
(Remember that visiting one website can lead you to many other useful websites because they offer link/article suggestions or "Read More" or "Learn More" links.)
#1. King Arthur's Knights
Within it you will see a tab "Arthurian Characters" that will help you as well.
#2. The Arthurian Legend
Other links per character: