First go to your router's settings and under "connected devices" locate your RPi. Note its IP address which will be something like 192.168.0.23.
Once you know the IP address of your Pi, open a browser on your Desktop or Laptop (which is connected to same router as Pi), and enter following address in browser's address bar
This will open a cinfiguration page. Complete configuration settings. You will need sharecode whichwas emailed to you when you first reggistered your Pi.