preset movements

Unity Engine
1

Hi guys, Im looking for a good way to how set commands for a character control.

I.E.
down, forward and a button do something, or back, forward and a button

any idea how to code it?

thanks a lot

2 
void Update()
    {
        if (Input.GetKey(KeyCode.W))
        {
            Vector3 position = transform.position;                                  //  transform current position
            Vector3 forward = transform.forward;                                    //  3d direction the transform is looking at.
            transform.position = position + forward * speed * Time.deltaTime;       //  moving forward
        }
        if (Input.GetKey(KeyCode.S))
        {
            Vector3 position = transform.position;                                  //  transform current position
            Vector3 forward = transform.forward;                                    //  3d direction the transform is looking at.
            transform.position = position - forward * speed * Time.deltaTime;       //  moving backward
        }
        if (Input.GetKey(KeyCode.D))
        {
            Vector3 position = transform.position;                                  //  transform current position
            Vector3 forward = transform.forward;                                    //  3d direction the transform is looking at.
            Vector3 right = new Vector3(forward.z, forward.y, -forward.x);          //  2d clockwise perpendicular vector to (x, 0, z)
            transform.position = position + right * speed * Time.deltaTime;         //  moving to the right
        }
        if (Input.GetKey(KeyCode.A))
        {
            Vector3 position = transform.position;                                  //  transform current position
            Vector3 forward = transform.forward;                                    //  3d direction the transform is looking at.
            Vector3 right = new Vector3(forward.z, forward.y, -forward.x);          //  2d clockwise perpendicular vector to (x, 0, z)
            transform.position = position - right * speed * Time.deltaTime;         //  moving to the left
        }
    }

Some simple 2d movement on the xz plane.
This should get you started