Settings › users is everyone in the organisation. Company admins create operators and other company admins for their companies.
The top of Settings is your own account. Users is underneath. Operator works the machines. Company admin also manages users, notes and the install link.
Press create. With an email as username they get a 7-day invitation to set a password. A non-email username gets a temporary password shown once. Do not reuse a mailbox across people.
Choosing company admin on that same menu is Invite someone as a company admin. There is no self-serve password reset. Issue a temporary password from this table. Sending the link again is Send the invitation again. Disable a person's sign-in is the last button on someone else's row. Require an authenticator for a person is on the same row. Replace a script key is the other button. The key is not how they sign in.