Can we build advanced forms with Marketo? Forms with IF and THEN rules. Any tutorials to learn how to build them?
Please be precise about the desired business logic and how it differs from Visibility Rules.
Most any "advanced" functionality can be built with the assistance of the Forms JS API, as you can see by searching the Community. But it's impossible to give suggestions with so little detail.
Like Sandford said, you can use Visibility Rules on each form field to effectively create If/Then rules as your suggesting, but that absolutely has limitations. If you care to share more about your scenario, happy to try to comment.
Retrieving data ...