You were invited to this Switchyard.
On an iPhone: if the phone shows “Choose how to manage your passkeys”, it has no passkey store selected yet. In Settings › General › AutoFill & Passwords, tick Passwords (or Chrome) under “AutoFill From”, and if Passwords is not listed, turn on iCloud Keychain first.
Your account starts with the whole corpus to read and nothing of anyone else's. Your notes, findings, evidence and working sets are yours alone.