Ambience/Background noise

How does one going about setting up different ambience sounds for certain areas of the terrain, ex/ Near a shoreline gulls and the sounds of waves, On a space station with sounds of the engine humming ect.

Unity has the ability for you to create Audio Sources. These are attached to Game Objects in 3D space, and can emit sounds. Your Audio Listener attached to your camera, when moved around the world, can interpret the sounds it "hears" from the various audio sources around the world, playing back audio using realistic panning and volume settings.

In laymen's terms, an Audio Source is a speaker. You can set its volume and rolloff factors to achieve the desired effect you want. And an Audio Source (typically attached to your camera) acts as your "ears", "listening" to the world around it. Any sounds it "hears" get played through the game audio.

AudioSource

AudioListener