As an example, I will take a Netis WF2411E router with the firmware version 2.4.41346 installed and update it.
1) Open the router settings by typing the address http://192.168.1.1 (maybe 192.168.0.1) in the browser and enter the login/password, by default the login is admin without a password.
2) Download the new version from the official website
http://www.netisru.com/Suppory/de_details/id/1/de/37.html
At the time of this writing, I downloaded the file netis(WF2411E_RU)-V2.4.43240.bin
3) In the interface that opens, open the “System Tools” menu, select “Firmware Upgrade”, in the window that opens, click “Browse” and select the previously downloaded firmware file, click “Upgrade” to starting the update process. We are waiting for the completion of the process for about 2-5 minutes.
When updating the firmware, do not turn off the power supply of the router, as this may damage the device and may need to be restored via TFTP.
After updating the firmware, in my case, the router settings were reset to factory settings.
See also my article:
How to upgrade the firmware of Netis WF2411