Can I make conditional fields

Hi,

Please check this user guide on Smart Forms using Condition Logic

Is this what you were looking for?

Please let us know if you need further assistance.

Thanks.

Addition :

If I am not mistaken, I think what what you wanted to achieved was to make a field required or not required base on condition. 

You can use the option "Require a form field" option in the Condition Logic wizard

Thanks.