Software is simple to install in Ubuntu, just use Software Centre or synaptic package manager.
I think you're struggling with simple things, because you've jumped in head first without reading up on how Ubuntu works.
Try googling first, and find out more about the operating system, or check here:
http://www.omgubuntu.co.uk/2011/10/1...-ubuntu-11-10/
http://www.techdrivein.com/2011/10/1...lling-new.html
http://www.unixmen.com/top-things-to...natty-narwhal/
The list is endless, and could save you asking unnecessary questions.