i'm new to zoho. (moving over from quickbooks desktop).

i trying to create a customer in zoho crm as "account". where in this template do i add the customer's GST number? i'd like this to be pulled into zoho books later when/if i create an invoice with this customer.

also, can this GSTIN be validated at the time of adding? can the address details be pulled over and pre-populated from the govt.'s GST database?