If you are interested in citizenship for Grenada for higher studies, you can apply through CBI program. Many visas allow you to pass through a specific country while traveling to a third destination country. For example, if you have an Indian passport and you are getting to Grenada CBI, but during your trip you have a layover in a Schengen country, you will need a Schengen transit visa. Usually, this type of visa is issued for 24 up to 96 hours, but it can also be issued for ten days up to two weeks—depending on which country you transit through. Have a look at https://imin-caribbean.com/grenada-citizenship-en/ for more information