form with dinamic dropdown , form should save the the options

[login to view URL] i need a form with dinamic dropdown (if i select contacts in the first dropdown should contacts name in the second dropdown) , the form should save the options. Taks: 1) create a form with 2 dinamic dropdown 2) option in the first dropdown: Contacts , Property, Opportunity, Transaction, Forms, Documents ( there is one table for each option) 3) save that information ("emails_related" table and update emails "related" field to "Yes" 4) back to the home screen "emails_related" table fields: 1) email_related_id (just autoincremental id) 2) related_name_with (can be Contacts , Property, Opportunity, Transaction, Forms, Documents) 3) related_id (id of the contact , or id of the property....) please check the screenshot link [login to view URL]