Before configuring, please obtain the IP.
Refer to the tutorial: [Two IP Extraction Methods]
1.Open Settings, tap on WLAN
2.Find the connected WLAN, tap on the small icon on the right
3.Tap on Configure Proxy option
4.Choose Manual, fill in server and port
5.Turn on the authentication button, fill in username and password. Tap on save in the upper right corner, configuration completed.
6.Search for IP address in browser to check if it matches the configured proxy IP, then the proxy settings are successful.