I am an Indian citizen currently working in UK. I pay 11% of my salary to UK National Insurance in addition to the income tax. Can I claim any of it back when I go back to India?
No, but you should be able to eventually claim a UK state pension built up during your stay in the UK. Note for a full state pension you need 30 years contributions and only full years count.
Note there is also the Additional State Pension based on your NI contributions. There is no fixed amount like the basic State Pension.
The following page might be of help