how to change brakes front and rear

tell me how to do it

Its hard to describe accurately without you having images. On Youtube there are several pretty good videos showing brake pad replacement on vehicles similar to yours. For proper instructions specific to your truck there is a company that independent auto repair shops "buy" their information from that offer a very reasonable service to do it yourselvers. You can get a one week subrcription or year subscription very cheap. The information is year make and model specific repair procedures, service bulletins, component locations, wiring diagrams ect.... great quality information same as the professionals have ,much better than generic workshop manuals from parts stores, much cheaper than the factory manual try http://bit.ly/mitchell_repair_manuals_online and get an online repair manual subscription.