np. Configuring controllers is explained here - https://github.com/retropie/retropie-setup/wiki/First-Installation - configuring additional controllers is under the "start" menu in ES (as you have found). Once configured in ES other emulators are set up automatically etc.
Contributions to the project are always appreciated, so if you would like to support us with a donation you can do so here.
Hosting provided by Mythic-Beasts. See the Hosting Information page for more information.