This is also a good starting point
PS: A bit off-topic but if your budget is very low you can try i.e.
GitHub - radio24/TorBox: TorBox is an easy to use, anonymizing router based on Raspberry Pi, which also runs on Debian and Ubuntu based systems. or GitHub - necro-nemesis/LabyrinthAP: Gain access to Lokinet and the internet connecting via an SBC based access point. this will run with RPi 4 or even smaller SBC.