Hi @Kali-Williams ! I think what you have here is a good start. It definitely shows the panic of the geese. I think if you have your grandmother at more of an angle to our left (or flip her to face the right) you'll be able to show more of her arms holding the gun outward and the stream of water coming from it.
Some other thoughts:
If you were to elevate or lower your camera's view, you could pull back and show a car close to the camera (as if the camera was looking over top of it or off to the side). This would help show the geese were blocking the way as they're flying up from the walkway.
You could do a reverse angle, as if looking out the door, and grandma would be close to the camera as we look down the gun, the water, geese flying away from us revealing the car in the distance.
On the topic of composition - one of the coolest exercises I learned in art shcool was the teapot and teacup. Take a sheet of paper and layout a grid of duplicate squares. Then use each square to come up with a different composition of the teapot and teacup together in the same scene. Do as many as you can possibly think of, then do some more. We used to do about 50 to 100.
ref 1 (you can do smaller 1 inch squares; these are meant to be thumbnails):
ref 2 (example of the exercise):
Hope that helps!