Forms such as the contact form are created using the Formidable plugin. All form submissions are stored in Formidable>Entries in the left menu.
To edit any form go to Formidable>Forms and click Edit
. 
For complex forms such as hidden fields which display depending on previous answers, calculation of a total amount based on the sum of all inputs, etc please contact Elan Creative to implement your requirements. Teaching how to create and edit complex forms is outside the scope of our quick reference, easy-to-use FAQs.