how to add force to up in unity c# code example

Example 1: unity how to add force

public Rigidbody rb;

if(Input.GetKey(KeyCode.W))
{
	rb.AddForce(100, 0, 0);
}

Example 2: how to make rb.addforce 2d

public Rigidbody rb; //make reference in Unity Inspector

public float SpeedX = 0.1f;
public float SpeedY = 0.5f;

rb.AddForce(new Vector2(SpeedX, SpeedY));