how to return to the original text message after replying to a specific message?

Hello Lizkin33.

Thanks for reaching out to Apple Support Communities. We understand that you need help with navigating Messages back to the previous screen, after replying to a specific message. We will be glad to assist.

After replying to a specific message, just tap a blank area of the screen. From here you can continue the message thread or tap the back arrow in the upper left to go to the message list.

Cheers.