Hello Corbmeyer,
Thank you for using Apple Support Communities! I understand that you're unable to send GIFs from your iPhone XR. You've come to the right place for help.
Let's start by going to Settings > Cellular, scroll down and confirm that Hashtagimages is enabled. From Settings > Messages, confirm that MMS Messaging is enabled. After that, try to send a GIF following the steps here:
Send and save GIFs on your iPhone, iPad, or iPod touch - Apple Support
If you receive an error message when sending a GIF, the following support article provides some additional troubleshooting steps to try:
If you can't send or receive messages on your iPhone, iPad, or iPod touch - Apple Support
Keep us posted on the results.
Cheers!