Multistep form request session

Hey Guys,

I wanted make a multiple form. In first step I have form with - first, last name, company name, street, house number. In second step I have e-mail, phone number and someone message.

How I can make array with all data from field form?

public function createFirstStep(Request $request)
    { 
        $data_form = $request->session()->get('first_name');
        return view('contact-form.first-step', compact('data_form', $data_form));
    }

What I can write in get() parameters to get all field data?