I bought a new iMac 27inch with track pad. Now some of the features I enjoied with mouse are missing.
How to do right click or left click on track pad?
Yes, you certainly can. You can assign the lower left or lower right area of the Trackpad to act as the right click and you can also check "Secondary tap" under the Two finger options. This means that whenever you tap two fingers at the same time, the system will recognize that as the right click.
It's very easy to configure what you want one, two, three, and even four finger tapping and swiping to accomplish. System Preferences is where these configurations are made.