To connect a Playstation to the Wifibri PPPoE network you can use the following steps

First you connect the playstation wired to the wired Wifibri public network, then go to Settings

In the Settings menu go to Network

In the Network menu, go to Internet connection setup

Select Use a network cable from the following menu

Then click on Custom

In this list you choose PPPoE

In the PPPoE menu you are able to enter your data. Then click next and the Playstation should connect to the PPPoE network