A singing teacher can work with you to develop your voice whatever your current skill level.
The singing teacher will listen to your voice and give you simple drills and teach you techniques to match tones and project your voice better. If you've ever feel nervous or self conscious about singing then a singing teacher can help you.
Singing really isn't as hard as you may think. Many people consider themselves to be great singers yet have never really listened to their own voice! Recording yourself singing and then playing it back can be quite a brutal lesson in how what you hear isn't what others hear. A singing teacher is trained to recognise pitches to a high degree of accuracy and will be able to correct and train your voice to match scales whilst increasing your dynamic range.
Singing is one of lifes great pleasures. Don't let your fear of singing hold you back.