For Android and I assume iPhones too, there is a secure messaging app called Signal.
It’s not owned by Facebook or Google or Microsoft. It’s very easy to use.
It’s more secure than email. For example, gmail is encrypted, but Google tracks your keystrokes when you write your email. After that, then and only then, others can’t see your communication.
No one is required to use it. But the other two big messaging app’s, Messenger and WhatsApp (outside of the US, mostly) are both owned by our trusty friend Facebook.
Secure encryption is only working if both parties are using Signal, otherwise it’s not got the higher level of security.
Signal was very hard to use when it first came out. Now it’s a breeze to setup.
I am posting this signal channel (group) only for Texans. Other states will do as they choose to. Texas is truly huge and traveling to a chapter meeting in Houston from Amarillo is a two day drive. Not practical.