To change openwrt luci web ui port on your router having openwrt.
Open Winscp (https://winscp.net/eng/download.php)
Go to `Session` => `New Session` menu
Select File protocol: SCP
Enter Host name: 192.168.1.1
Port Number: 22
User name: root
Password: YOUR_ROOT_PASS
Hit `Login` button
Then navigate to `/etc/config`
Open the uhttpd file in Notepad
Change the “:80” and “:443” to your desired ports, in following config I have changed the http port to “801” and https port to “4431”
In notepad, go to file => save menu
Close notepad and restart your router.
Now you can access the LUCI web interface on port 801
