From_for Rails #new => #edit

I would like to use a form in Rails. To be more specific; I would like to have 3 cascading drop downs lets say Brand Year and Model on the #new page. Then when I click Next or Proceed Button.

It has to come to another longer form (where I will use wizard later on) on #edit page with 3 text area auto filled the data selected from a #new page. (people can write or erase the auto filled data)

I know there are ways to submit to data to another form with auto filled option. But I am a bit confused with controller actions. As Rails sends to #new action the to #create I do not know how I can render #edit page.

What I think, in the #create action we might root to #edit action from there but I am not sure.

Thank you for your help!