I want to configure SQM and it probably has been asked 100 times but someone please help

sqm/cake needs considerable CPU power, more than ipq4018 can provide; you are firmly in x86_64-land (or RPi4) for sqm at 500/500 MBit/s.

There are quite a few 4-port 'firewall mini PCs' on amazon/ aliexpress starting around ~200 EUR/ USD, examples for cheaper options can be found here: