You didn't mention whether your Rebel was a film version or digital, but as best I can see from the manuals they are quite similar with regards to your question.
The camera does have a light metering function, but you won't see a needle like some of the older film cameras had. Instead, you will see in the viewfinder the shutter speed and the aperture settings. For example, 500 4.5 would indicate that the camera has determined that the shutter speed will be 1/500th of a second and the aperture f/4.5 to properly expose the shot. Depending on what mode you are in, you can control one or both of these numbers. If either number (or both) are flashing, it indicates that the shot will be overexposed or underexposed, and you must take some type of corrective action that the camera cannot do itself with the current mode settings.
Canon has manuals available online for all the digital Rebels and many of the film Rebels. See this link
. Select EOS (SLR) Camera Systems in the top box, and choose the appropriate categories in the next two boxes, then click Go.