Sound synthesis is the process of producing sound. There are a lot of techniques to do so, analog or digital, and many subcategories such as subtractive and additive synthesis or granular and software synthesis.
How To Make It In The Music Industry - The cold hard truth by Greg Savage. They'll never be a deal written with your best interest in mind unless you have something the label needs and can't get anywhere else.
Record a flawless track even if you keep making mistakes. Here's how to do it using Reaper (though the process is the same with any recording software): Quickly Fix Audio Recording Mistakes by Overdubbing