Have you been told you cant?
Would you like to join a choir or strengthen your existing technique?
It helps to think of the voice as a piece of engineering or an unstable wind instrument. When it doesnt work as well as we think it should there is usually a mechanical fault which can be fixed with very few exceptions.
Often the instrument is perfectly sound but the singer needs to learn about their voice in order to play it well.
I use a mix of disciplines to help my students to achieve this; Estill (for pure understanding of the mechanics), Bel Canto (to strengthen the actual voice), Alexander Technique (posture and alignment) and Smithing (for breath management
Lessons should be hugely enjoyable and consist of simple vocal exercises for about half the time followed by songs and/or harmony ear training to make sure that skills learnt can also be applied to repertoire.
Older voices respond well to lessons especially where there is no previous experience. However, even the worst ingrained bad habits of a lifetime can be unlearnt with a little patience and willingness to play with the voice at home now and again.
I am a classical singer myself but also trained in Music Theatre. I recommend trying a bit of everything if you are a complete beginner.
Studios in Eden Park, Beckenham and Marble Arch (near Oxford Circus), other areas covered, for further info please visit my website.