Contact with your purchase item author hope they will helped!
This would almost be a customised form, or using one of the online applications such as docusign. If you are not prepared to pay for an esignature form element, then perhaps create a form whereby the user reads your terms and conditions, click YES I AGREE and then you get an email saying something like:
Name: Joe Bloggs
Email: their email address
IP Address: logs the IP address of the person concerned
Date: shows the date and time of their form submission
I agree with your terms and conditions etc etc etc
I don’t know if something like this would be suitable for what you need or want