Can you go all the way back to the beginning, please? Pretend that you have never heard the words redirect, rewrite, root, host, directory, htaccess et cetera. You are allowed to use the words "address bar" (as in the user's browser) if you need to.
Now just explain in English
#1 What the user does
#2 What is supposed to happen when they do this.
Repeat for each different set of actions. Make up two or more examples for each pattern.
It may or may not be helpful to show a few cases of
#3 Things the user might do that are OK the way they are and don't need to be changed in any way.