I want to help in coding!

In order to commit to bazaar (bzr) branch of lp:timekpr you have to be a member of timekpr-maintainers:
https://code.edge.launchpad.net/~timekpr-maintainers

If you are new to bazaar *please* test bzr and how it works in a personal branch first:
http://code.launchpad.net/people/+me/+addbranch

Also, read the 5-minute tutorial for bazaar version control system - it's an excellent introduction:
http://doc.bazaar-vcs.org/bzr.dev/en/mini-tutorial/index.html

Finally, if you want your commits to show up in the IRC channel, follow this guide:
https://answers.edge.launchpad.net/timekpr/+faq/413