I am only interested in 2 languages.
English and Cherokee Indian.
I don't know if it will matter if I use UTF-8 or not.
Cherokee has it own font if thats any help....
Also, if someone changed the site to Cherokee and did not have the font installed.
Duse the site have any kind of check or warning for that?

No, and that's why you should use Unicode. With Unicode, anyone in the world would see your site in Cherokee, whether they are Cherokee or Chinese.