Hello Cantgetausername,
Welcome to Apple Support Communities. It sounds like the native Messages app is having issues and is frozen. Right?
We'd recommend the guidance from If an app on your iPhone or iPad stops responding, closes unexpectedly, or won’t open - Apple Support. Keep in mind that not all steps, like deleting and redownloading, will be possible since this is a native app. Applicable steps are as follows.
1 Close and reopen the app
Force the app to close. Then open the app to see if it works as expected.
2 Restart your device
Restart your iPhone or restart your iPad. Then open the app to see if it works as expected.
3 Check for updates
To see if updates are available for the app, open the App Store, tap your profile icon, then scroll down to see if updates are available. If updates aren't available for the app, update the software on your iPhone or iPad.
If the same continues, as that article mentions, it will be best to reach out to the app developer in which this case is Apple. You can reach out from Apple Support.
All the best.