Yes. Especially for those who are going to face IIT interviews or going to join there, these are very beneficial. Advantage of having linux is it provides an easy environment for programming. So lets see how to use it. I'll give some exercices as answers here. You can try them and comment as required..
the above command shows help for "cp" command. Like this you can do for any command. So, first one- simple.
Copy a file a.txt to b.txt. Then concatenate both and output as c.txt. cat command might be useful. Also google for more interesting options.
opens a terminal in Ubuntu and you start from there. gedit a.txt opens a file and if you do not have GUI, you can use nano a.txt