Restore text messages
How do I restore the text messages I accidentally deleted
iPhone XR, iOS 14
Question marked as
If you were using Messages in iCloud, then I am afraid they are gone for good:
Use Messages in iCloud - Apple Support
If not, then you would have to restore your device from a backup that has those messages:
Restore your iPhone, iPad, or iPod touch from a backup - Apple Support
Be aware that restore is an all or nothing process. You cannot restore only messages (for example) and any information on your device between now and when the backup was created will be lost.