Do I also need to have a Visit Invitation for Any of the schengen territories to apply for a Visa? Kindly let me know this, or I could just apply for a Vacation and I am good?
What you need is an explanation of why you travel, and documents supporting that explanation.
- If you are a tourist and pay for the trip yourself, you need no invitation.
- If you are visiting friends who provide housing and food, they should confirm that.
- If you are visiting a company or a scientific conference, you should have documents for that.
When you come for a vacation, you have to document that the money is yours to spend, that the amount appears reasonable for your financial circumstances, and that you have ties (best a well-paid job) to return to.
They will want to see your finances in any case, to judge your ties to your homeland.