Question:

When I sing my voice is shaky; how can I make my voice stronger?

Answer:

You will need to work with connecting the strength of your entire torso with the way in which you manage the flow of air through your vocal cords and you will have to bring your vocal cords together robustly enough to produce a strong, even tone. In other words good posture, strong breath support and precise phonation result in a steady voice. This is something a singing teacher or voice coach can help you with.