for using the trackpad to click (and right click) instead of having to use the click button below the track pad, go to the apple at the top left of your screen. click that. then choose "system preferences". Then choose "keyboard and mouse". Then under the tab "trackpad", make sure that the box next to "clicking" is checked.
i like this feature because you can "click" with the track pad OR with the button, whichever you feel like using
but for some people, it takes a bit to get used to using the track pad for clicking because you accidentally click it sometimes. but i RARELY ever click it accidentally, as you just kinda get used to it
i had always used windows until i met my husband, now i am an apple addict
here are a few screen shots to help you visualize what I am talking about