If you want to use your Canon TR8520 printer wirelessly, connect it to a Wi-Fi network. The connection process is simple and quick, but before you get started, learn a few important things. Ensure your printer is powered on and that no error is displayed on its LED screen. Check that your Wi-Fi is working properly and that you have the necessary information, such as the Wi-Fi name (SSID) and password.
Disable VPNs or firewalls for a while because they may disrupt the printer’s WiFi connection. Moreover, have a computer, mobile, or tablet at hand to complete the setup process if required.
Follow the instructions below correctly to have your Canon TR8520 printer successfully connected to a wireless network:
Turn on your printer.
On your printer’s home screen, tap on the Settings icon.
Select Device Settings from the list.
Under Printer settings, choose LAN settings.
Tap on the WiFi option.
On the WiFi screen, select WiFi setup.
In the WiFi setup, select “Manual connect.”
The printer will take some moments to detect the available wireless routers.
From the list, choose your WiFi name.
Tap the “Please enter” field to enter your WiFi password.
At last, enter your password and tap “OK.”
Source:- Connect Canon TR8520 Printer to WiFi