Hi, @comptedev.
Glad you reached out.
You have two ways to do that:
1. Custom code
Using some custom code, you can add as many fields as you want to your forms. We explain it here https://givewp.com/documentation/developers/how-to-create-custom-form-fields/.
If you need assistance implementing custom PHP code on your website we have this guide:
https://givewp.com/documentation/resources/adding-custom-functions-to-your-wordpress-website/
Please note that this code snippet is provided as an example of how you can extend GiveWP with code. It’s up to you to implement and customize to your liking. We cannot provide support for custom code on your website, only the code that we create and distribute.
2. Form Field Manager add-on
If you decide to use our premium add-on, you can create these fields without the need to use custom code.
You can learn more about it here:
https://givewp.com/addons/form-field-manager/
https://givewp.com/documentation/add-ons/form-field-manager/
Thanks for using GiveWP! Have a great day.