Creating my own fields

I want to figure out how to create my own fields like for car information. If I wanted them to give me the make model and year I want three boxes in one section they can enter that info into. Right now I have the make and model in a full name type of field... I guess I just cant find the custom way yet. Thanks!

Inside of Form Builder you can add fields and create your form. This guide can help you to create your form: http://www.jotform.com/help/2-How-to-Create-Your-First-Web-Form 

In case that you want to achieve something else can you please explain in more details your request and provide is ID of your from?

Hope this will help. Let us know if you need further assistance.