1st Time Set UP of GL-MT3000 request for assistance

When Setting up GL-MT3000 Beryl AX for the first time, how do I find the Administrative panel Password to start??? and do I plug my ethernet into the router as well as the the ethernet cable I plug to my laptop

There is no password for the initial login. The device will ask you to create a password.
See First time setup - GL.iNet Router Docs 4