API Zoho CRM

API Zoho CRM

Hello,

I want to update the date of birth of my contacts. For now, all my contacts have an empty date of birth. I want my contacts to update this information themselves.

So I think go through the API but I do not know exactly how to do it.

I think we need to create a form with a "date of birth" field. This form will be opened by the contact itself via a URL that it will receive by email. In the URL there must be a way to customize the form with a hidden field containing the contact's ID (for example).

How to automate a script that retrieves the contact ID and then update the contact's birth date in Zoho CRM?

Thank you

EDIT : IT'S GOOD 
The solution :  https://www.youtube.com/watch?v=_KwTSiYnm6A&feature=youtu.be