If you want to limit your form to people who have a password, activate Require a password in the "Password protection" section and set one.
Once activated, anyone who opens your form link will first see a screen asking for the password before they can answer anything in the form. If the person enters the correct password, Can Do saves that access in their browser for one month. As long as that time hasn't passed, it won't ask them for the password again.
Things worth knowing:
- If you deactivate Require a password, your saved password won't be deleted, it just stops being requested. If you reactivate it later, it's still saved in Can Do.
- If you have a custom domain activated and you deactivate it, your password will be deleted along with it (see Using a custom domain with your Form). In any other case, they work separately.