What's the best OPSEC for teams?

Hacking groups have moved from casual to nation-state threat actors. Is Physical OPSEC better than digital OPSEC? Are both equally important? Meeting in-person to hack is probably better than using online encryption unless your encryption is unbreakable by the NSA's God-like quantum computer. But there's also the risk of one person ratting out the entire group to the feds. Trust is essential when doing cyber-security simulations, between red/blue/purple teaming. How the fuck do you teach someone to use a terminal? Can't do much without a CPU. Anonymity is key, if a group is decentralized and anonymous and only operates through IRC (centralized but anonymous) then maybe? Hidden services are good if they are hidden and people within the team know how to access said hidden service. Faraday cages and specialized wifi router security and firewalls are also equally important.

Any advice?

There's a .onion called the opsec bible you can find somewhere. Not the Darknet bible the opsec bible. It covers physical and digital security. Best one I've ever seen.