Hello people,
 
I'm new to Sonar, so I would appreciate it if you could help me out.
I'm trying to mix my vocals for a song, but when I import the audios to Sonar Studio, I can only hear "track 1" playing.
And track 2, track 3 etc. are just muted for some reason. That's not what I want, so anyone knows how I can get it right?
 
Thank you

Welcome to the forum.
Set the outputs of each track to the same output that track one is using.

How do I do that?
 
Also there are no "waves" on the tracks after track 1. But there's actually audio on the files, just can't see it in Sonar.

Are they Audio tracks?
You'll have to learn the difference between Audio, MIDI and Instrument tracks.
Defaults:
Audio Tracks have a 'sound wave' icon.
Midi Tracks have a 'MIDI plug' icon.
Instrument tracks have a 'piano keyboard' icon. 
 
In the left hand window of TrackView (Track Pane), in the blank space below the tracks, Right Click > Insert Audio Track.
On each track/clip on the right hand window of TrackView (Clip Pane), Right Click > Import Audio ...
 
http://www.cakewalk.com/Documentation?product=SONAR%20X3&language=3&help=Views.02.html
 

If you don't know how to set track outputs it's really necessary for you to spend some time reading the manual and doing the tutorials.
And this is the wrong forum...This one is for <8.5

Thank you all for your help. I figured it out.