Most game development (game design, art, programming, etc.) can be done by one person with relatively little equipment: A game designer needs a pencil and paper, an artist Photoshop or Paint, a programmer a laptop and compiler.
Sound is different: External noises are a big problem, sound effects can't be made with instruments, and small mistakes easily produce disaster.
I can see how large companies with big studios and budgets do this.
How can I do this as a one-man indie?
Should I synthesize everything? Record sounds and buy some crazy program for editing them?