It is pretty easy. If you join a club like "Nissanclub.com" you can even find out how in pictures. They have a how to section depending on the year of your particular vehicle.
Yours is in the 2007+ section.
how to change a brake light on 2002 Nissan altima
http://www.paulstravelpictures.com/Nissan-Altima-Rear-Brake-Light-Bulb-Replacement-Guide/Nissan-Altima-Tail-Light-Bulb-Replacement-Guide-011.html here you can see every step to that question.. I just did it.. and works :) by Paulo Fernando!!
low brake fluid
brake light and battery light is on
How to replace a brake light on a nissan Tiida hatch back.
how to change the rear tail light bulb on a 2004 Nissan maxima
smash it in wi a hammer
The 1998 Nissan center brake light is a sealed unit. The entire brake light unit will need to be replaced. Remove the wiring harness. Remove the brake light retaining screws. Reverse the process to install the new brake light unit.
Check brake light switch - could be defective or not aligned properly
fog light not working and radio light went out
Nissan altima 2001 hesiates at stop light?
no if your battery light is on and the brake light on then your alternator need to be change