How to use SQM QoS for fair bandwidth distribution?

I am new to OpenWRT, I am using TP-Link 841n v10, LEDE with SQM QoS,
I want to provide fair bandwidth to all of my user (< 10 users).
How should I configure SQM, in which interface should I use SQM , LAN or WAN??, I have all users connected via ethernet, i have bandwith of 45Mbps from ISP,

Just follow the general SQM instructions, https://openwrt.org/docs/guide-user/network/traffic-shaping/sqm and then the "sind and dance section of https://openwrt.org/docs/guide-user/network/traffic-shaping/sqm-details
Let us know whether that worked....

LEDE is not supported anymore, you should update the firmware. According to the techdata page, OpenWrt 18.06.8 is supported on this device. But also note the warning about low flash and RAM at the top of the page.