Dear Peggy,
Good day! Thank you for posting your query in our community.
Based on your description, you want to change the question type from Text to Choice. As far as we know, there is no out of box way to meet your requirement.
Many people have voted for this feature in this UserVoice: Change question type · Community (microsoft.com), and the Microsoft Feedback Team has already noticed this requirement.
Appreciate your understanding.
Sincerely,
Jazlyn | Microsoft Community Moderator