Contacts app: that is password protected, encrypted?

I have pretty much exactly the same question which was posted on Jan 18, 2021, by another party.

I know, the future is the cloud. However, I am not interested in something linked to an e-mail account, neither to the cloud, as for when private and sensitive data comes up.

I'm looking for an app. Example: former Palm's OS for managing Contacts, Notes, Agenda, even To-do list. A SIMPLE password to encrypt or mask data.

That's it. No more than that.

I would like Apple's Support Development department could take this case.

• Thanks in advance for your cooperation.