Is there any rule to make OAuth Redirect URL?

except for localhost it must be over SSL

RedirectURL is where you send people after the oAuth dialog to complete the oAuth flow and obtain/use the accesss token (depending on oAuth flow type)

In my implict auth example the redirect URI is https://barrycarlyon.github.io/twitch_misc/authentication/implicit_auth/ For example

https://barrycarlyon.github.io/twitch_misc/authentication/implicit_auth/