Hi there @MarqHardon ,
Thank you for posting on the Instructure Community!
In free for teacher, the only person that can change the name of your student's account is your student that has access to the account. Account Admin permissions are required to edit the user details of other users, and since free for teacher does not provide you with access to admin permissions, you will need your student to edit their name for you. You can also reach out to Canvas Support, however for a simple matter like this, I don't find that necessary.
Upon your student updating their name via their account settings, the name will be updated automatically on your roster. I recommend checking out this link for more assistance, if needed https://community.canvaslms.com/t5/Troubleshooting/Updating-my-displayed-name-in-Canvas/ta-p/853
Best,
Noah