I’m looking to be able to create logic-based drop-down selections (think car sales websites, where each selection influences the next options), where the information should be kept in a database and in the end, the selections should be able to be added to a page or cart (think the way dominos pizza shows your pizza creation at the end and adds it to a cart).
I found similar posts on this where they recommend using jotform for the drop-down forms or Isotope jvs, but nowhere about how to add all the selections to a cart or final page.
Please let me know if I made this clear enough or if I should try for a longer explanation.
As far as instructions, I would check the jotform site (or other service) on how to add such a thing to a Website and start from there. If additional custom code is needed, it can either be done yourself or perhaps find a javascript/jQuery coder who can help with that.
From the description, it does sound like a pretty specific set a features you are looking for, so probably a good start is to write down exactly how it should work and then check if the third party service will meet each requirement, and if so, to then search the third party service documentation on integration instructions.