How to make a car fly

i am making a harry potter stile game for my I.T project and i have gotten really far i just really need a script for the flying car, the controls could be:
spacebar makes it go up when you let go you go down the forward key moves you forward and the sideways keys make you move sideways, i think it would be best if maybe the car should fly through rings and maybe like after 10 rings it gets harder and maybe 5 sets of rings, but if that is to hard maybe they just have to follow an object in the sky (hedwig)

Give the car a rigidbody component. Then you need to code it. Won’t give a full script but I’ll tell you how to Add Force.

using UnityEngine;
using System.Collections;

public class forceTest : MonoBehaviour
	float force = .05f;
	void Update()
		    rigidbody.AddForce(Vector3.up * force, ForceMode.Impulse);
		    rigidbody.useGravity = false;
		    rigidbody.useGravity = true;

		rigidbody.AddForce(Vector3.forward * Input.GetAxis("Vertical") * force, ForceMode.Impulse);

You will also need some max height settings and such, but this will get you started with physics. Unity Script Reference - Rigidbody