Courtesy of @Happy2Play:
Here are the steps to creating a Collections library on a new install.
On the server dashboard at the bottom of the page there is a link to the API. Note there are connections requirements of using localhost or a HTTPS connection.
But there is a workaround with browser flags to allow your LAN connection from any address.
In Chrome/Edge entered IP or Hostname depending how you connect. edge://flags / chrome://flags (but other browsers sh