School choirs and musicals provide good early vocal training. Also, rock musicians can gain good practice playing in a school community band, or with a group of friends. It helps to grab every chance to appear in front of others. You may be able to perform at weddings or other events. Although voice training helps most singers, including rock musicians, creating or copying a popular style of music is likely to determine the success of a band.
Rock musicians have to be able to go on stage in front of lots of people.
The future Competition for all musician jobs is keen. That is especially true for rock musicians. Talent alone is no guarantee of success. The glamour and very high earnings in this job attract many people. You need a lot of endurance.