Start with a simple form

Make a form that asks for a number on page 1 and two colors on page 2 and returns the values entered. The first FormFunction argument is a list of pages, and each page is a list of controls:

Deploy the form to the Wolfram Cloud

Deploy the FormFunction to the Wolfram Cloud with CloudDeploy, specifying Permissions->"Public" to give anyone access to it:

Use the form

Click the link in the CloudObject output to use the form. The form’s function is applied to an association giving each form value and the value entered:

Make the values on one page depend on the values from another

Modify the form so that the first page asks for a number of colors, and the second page has one input field for each color. Return a list of colors:

Deploy the updated form

Deploy the FormFunction to the Wolfram Cloud with CloudDeploy, specifying Permissions->"Public" to give anyone access to it:

Use the updated form

Click the link in the CloudObject output to try out the form: