Defining a Manageable Scope for Ph.D. Research
The scope should be precise and manageable—"skill gap in India" is too wide an area to do justice in a Ph.D. thesis. It would be better if you can restrict it to a smaller geographical location, such as the National Capital Territory or Punjab.
Further, you may restrict it to a specific category of industry like the hospitality sector, insurance sector, manufacturing sector, etc. You may also focus on a specific group of the population, such as engineering graduates, commerce graduates, postgraduates, engineering diploma holders, ITI trained persons, matriculates, or non-matriculates. This approach can make the research more manageable.
You should also consider whether you will be able to obtain the necessary statistical data for such groups or sub-groups as mentioned above, like NCT/Punjab/hospitality sector/graduates, etc. Please try to do this and post here for further help.