How to delete the content of the sent SMS so that the other party's mobile phone can't see the SMS?

Classmate, once the message you send is accepted by the telecom company, it will be forwarded to the target mobile phone of your message immediately. This process is irreversible, which means that you can't let the other party see the message you have successfully sent.

Unless ... . . Unless you get the phone, delete it manually before the other party sees the message.

Or hack each other's mobile phones if you have the ability.