Enter the information you wish to save. In the “Other Significant Information” box, include items such as the login process, if there is multi-factor authentication (MFA), who are beneficiaries, and the logon link to the account.
If you have more than one account with the same institution, consider adding a brief description at the end. For example, “Fidelity 1111” or “TD Ameritrade Roth.” Each has an extension that describes the account and distinguishes them from others. To keep it simple, if you have all the accounts tied to the same institution with the same login credentials, then provide the different account numbers in the “Other Significant Information” to let loved ones or trusted advisors know you have multiple accounts.