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:

Out[1]=

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:

In[2]:=
Click for copyable input
Out[2]=

Use the form

Click the link in the CloudObject output to use the form. The forms 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:

Out[3]=

Deploy the updated form

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

In[4]:=
Click for copyable input
Out[4]=

Use the updated form

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