@kjleitch Hi and welcome to the forum.
What spec machine are you running Zorin Core 15.3 on?
Is it just the touchpad pointer, or are the touchpad buttons also not working?
You can test using Settings>Mouse and Touchpad see:
(sorry that screenshot not english language)
You could also look at these threads to see if anything helps:
You may need to update your Linux drivers… open your terminal and try:
sudo ubuntu-drivers autoinstall
Insert your password when prompted. Reboot and attempt to use your TouchPad again. If that still doesn’t do it you may need to upgrade your Linux firmware (prepackaged drivers with some of the features people asked for as well as bug fixes). This link will tell you how to install a newer version (1.19* as of this post) .