> "what if we have a family Computer but each wants to access their private accounts and keep the others from accessing?"

That's what OS level user accounts are for. Tbf

> "what do Ineed do to login from an airport computer?" or "what should do if my phone is stolen?"

Indeed I don't know the answers to these either if I wasn't syncing passkeys in 1password. Honestly we should educate people to use password managers more than any thing. It's also a smaller jump than to passkeys. Passkeys can be more of an advanced convenience feature after they get used to using password managers already.