Canon EOS Rebel T5i 18-55mm IS STM Lens Kit Manual (en)

Changing the Autofocus Method (AF Method)
The dedicated AF sensor is used to focus in One-Shot AF operation 
(p.98), using the same AF method as with viewfinder shooting. 
Although you can focus the target subject quickly, the Live View image 
will be interrupted momentarily during the AF operation.
You can use nine AF points to focus (automatically selected). You can 
also select one AF point to focus and focus only the area covered by 
that AF point (manually selected). In Basic Zone modes, the AF point 
will be selected automatically. You cannot select the AF point.
Display the Live View image.
Press the <A> button.
The Live View image will appear on 
the LCD monitor.
The small boxes are the AF points.
Select the AF point. N
Pressing <0> or the <L> button 
will toggle between automatic 
selection and manual selection.
Use the <S> keys to select an AF 
point. To return the AF point to the 
center, press <0> or the <L> 
You can also tap the LCD monitor 
screen to select the AF point. During 
manual selection, tap [
] on the 
screen to switch to automatic 
Quick Mode: f
AF point