I’m gonna advice you to practice too, but try following a regime…. practice scales, they expand your voice range a good deal.
Just a few tips I’ve learnt along the way being a chorister for about 15 years…
You can control your ‘louds’ and ‘softs with your abdomen muscles. Pushing them in will result in ‘louds’ while letting them relax will give you ‘softs’. Also, breathe with your diaphragm, because it really gives you the ability to hold on to notes for longer with a better voice quality.
First, though, you really need to know at what range your voice sounds good!