yesterday I installed ubuntu, I am not able to do anything even playing MP3 music in linux

After installing Ubuntu, I don't to how to proceed Sir,

Hi :)

After installing Ubuntu this worksheet really needs to be worked through
https://help.ubuntu.com/community/Medibuntu
I keep all the non-free components as they don't seem to cost anything. Perhaps that is just because i don't live in the USA tho. The medibuntu worksheet deals with all the copywrite issues for the country you are in at the moment. Hopefully all your multimedia issues will be fixed after working through it or at least the ground-work is done to help sort any further problems

Good luck and regards from
Tom :)

Hi all u need is a internet connection. Go to application->add/remove.... menu whis is int the top right corner. In Add/Remove dialog box in "show" label choose all available application, search text box type "ubuntu-restricted-extras" with out double quote.
Then u get ubuntu-restricted-extras listed below, tick the check box and click apply chances command button. then a application installed, then u can play mp3, divx, mp4, flv, flashplayer etc. then u r system become multimedia system.

Hi :)

No, that hardly even solves the immediate problem. Why avoid fixing almost all the issues in 1 easy go? It is much easier to follow the Medibuntu guide
https://help.ubuntu.com/community/Medibuntu

Regards from
Tom :)