I looked at that 30 day web site and maybe it can be useful.

However, I think the best way to start, is with in person lessons. A quilified teacher is the best way to understand your vocal prowess. They can watch you sing and help you with developing breath support. They can evaluate and help your tone quality. I sang for a lot of year before I took voice. I was astonished how much it helped me to understand the perameters of my vocal ablities and to develop them.