If you are looking to add a Yes/ No question field to your registration form template, you can do this from the custom fields section. You can create a new registration form or simply edit an existing one.  

To add a custom field with Yes/ No Question:

1. Go to 'Registration Forms'

2. Click on the registration form that you wish to edit

3. Go to Section 5 - Other (Custom Fields) tab

4. Click on the '+ Add Field' button

5. In the field type, select the option 'Yes/No' from the dropdown list 

Once you have entered the relevant details into the field, click on 'Create Field' to save the changes. 

Below is an example of a Yes/No question. Additionally, if required, you can also add instructions to your question in the 'Statement' box. For example, if the respondent's answer is 'Yes' then you can add a note asking to provide more information.