So if debayering is required to make a grayscale image a trichromatic image....why are my RAW images already colour?? Does that mean that the camera already did the debayering of the image?
It might have been the camera. It might have been the application you used to open the file.
When you open a "raw" file on your computer your see one of two different things:
A preview jpeg image created by the camera at the time you took the photo. The camera used the settings in effect when you took the picture and appended it to the raw data in the .cr2 file. If you're looking at the image on the back of the camera, it is the jpeg preview you are seeing.
A conversion of the raw data by the application you used to open the "raw" file. When you open a 12-bit or 14-bit 'raw' file in your photo application on the computer, what you see on the screen is an 8-bit rendering of the demosaiced raw file, not the actual monochromatic Bayer-filtered 14-bit file. As you change the settings and sliders the 'raw' data is remapped and rendered again in 8 bits per color channel.
Which you see will depend on the settings you have selected for the application with which you open the raw file.
Since you have a Canon camera I would encourage you to also try Canon's Digital Photo Professional for editing and converting raw files. It is included on the software disc that comes with every Canon EOS camera and updates are free from Canon at the support page for your particular camera model. Here's a link to the EOS 700D/Rebel T5i support page. Just click on Software to see a list of the most current versions of the applications available for the particular camera model. You can search for other models from here.
Canon's DPP actually reads all of the EXIF data including the "maker notes" section and by default uses the in-camera settings as the initial profile when rendering .cr2 files (something most raw converters do not do). The initial rendering of the raw data will be very close to the appearance of the jpeg preview generated in camera using the same settings. They will probably be so close that they will be indistinguishable to your eyes.