The answers to the custom questions you added to your sign-up sheet can be easily obtained by downloading an XLSX document.
How to export custom question response data
Locate the sign-up sheet from which you would like to export the participant response data
Click the three dot icon
Select 'Export'
Your sign-up sheet data will be exported to your 'Downloads' folder as an Excel document. Now you can easily visualize all responses, filter by respondent, time slot and more.