Hi Sandhiya
mojoPortal has the best documentation to help you on your journey.
I suggest you first install and use mojoPortal first. Play with all the features.
Then when you are ready go to Developer Docs.
Inside these documents are Training Videos. These 31 video's are excellent!
If you want to create a new custom feature using code behind it is relatively easy if you have MS Visual Studio. There are about 4 hours of video's and lots of fun things to learn. It is not hard, even a beginner programmer can do it. However there is no 1 hour short-cut.
Also. Every time you click on a (?) help icon in mojoPortal a messagebox pops up. You may want to explore the source code and see how it's done.
Hope this helps.
Rick