Definitely start working out and eating right as of yesterday. It will help your HRT to be more effective to be at a healthy weight, if only because being at a healthy weight makes everything about your body more effective. And naturally when it's time for surgery, it will definitely help with that too.
Voice work takes time -- sustained practice, and the right sort of practice. It's probably the most difficult thing we have to do. You won't get it down overnight. I worked on my voice for an hour a day, five days a week -- breathing exercises, pitch slides, diaphragm control, funny cartoon voices, intonation variance, "yoda" techniques, recording and listening, recording and listening, over and over again, and it's the worst because you can still hear how wrong it all is -- and it took about six months before the "aha!" moment when everything clicked into place. That was almost two decades ago, and I haven't been clocked on the phone since.
