@Levi-Macruz0,

When you are first setting up the router, the quick setup has the option to select the type of internet available to your home, PPPoE is one of these options. If you did not previously change this setting, then the setting will now be found in the dropdown under Advanced>Network>Internet. Here you should be able to see PPPoE as an option, it is most likely listed as a Dynamic IP right now

@Levi-Macruz0 

The PPPoE username and password should be given by your provider, they are not the login username and password. If you don't know that, you need to contact your provider.