Yes, systematic vocal training and good speaking habits can change a person's voice timbre, or at least improve it.

First of all, you must find a professional vocal teacher. A professional vocal teacher will know clearly your learning situation and what kind of training your voice is suitable for. At the same time, we will teach you how to conduct professional and systematic training. A good professional teacher is not enough. As the saying goes, "The master leads the door, and the practice lies in the individual." A good professional teacher can teach you good methods, but also the feeling of music, awareness of pitch, and understanding of music. Sensitivity must be trained over a long period of time. If a person who studies vocal music cannot even sing the music correctly or complete the pitch, he must be an unqualified vocal music learner. Therefore, sight-singing, ear training and music theory must be studied very solidly.