Zoho Creator/Portal, user logs in, data prepopulates from CRM

Zoho Creator/Portal, user logs in, data prepopulates from CRM

Hey all, I am looking to do the following:

  1. User logs into or signs up at the portal
  2. They are greeted with a standard form:
  3. fname   lname
    email
    phone
    address
    etc.
  4. If the user is in our CRM already (based on email address), the form would pre-populate name, phone, address, etc (if data is available). Otherwise would be blank. 
  5. If it was a new user, once this user fills out the form, the data would create a contact in the CRM.
Can someone give me some direction on #4, the pre-populate from CRM part?  I am certain it is possible, I just need a nudge in the right direction of how to do this.  I did find some previous posts related to this but they were nearly a decade old.

Thanks