Some of the Lenovo or other brand laptops are currently coming with in-build hotkeys functionality. As a programmer I need F1-F12 keys very often. And that's why I was looking for this solution.
Steps:
1) Open Lenovo Vantage app (Pre-installed)
2) Go to Hardware setting.
3) Click on hardware setting again.
4) On popup click on Input.
5) Now under function keys, select F1-F12.

You are done.