There are no direct flights between India and Puerto Rico. There is at least 1 stop to get to San Juan and most of the routes actually have 2. If you're not travelling from the major airports, you might even have a transfer within the country. Several airlines like the British Airways, American Airlines, Turkish Airlines, Etihad Airways and several others operate on routes between India and Puerto Rico.
Puerto Rico's main airport is the biggest airport in the Caribbean. The Luis Mu_oz MarÍn International Airport (SJU) in Carolina is connected very well by flights from several cities in the US mainland and also some major cities in Europe like London, Madrid and Paris.
Ferry services connect Puerto Rico to the US Virgin Islands and the Dominican Republic. These are very popular and scenic routes to get into Puerto Rico.
Getting around in Puerto Rico is no big issue. There are pre-paid taxi routes to all tourist attractions from taxi stands. Metered taxis ply in other areas of the island. Buses are also very well connected and so are publicos. These are popular ways to travel since they are extremely cheap and cover a fair amount of routes. A heavy rail system called Tren Urbano serves the metropolitan area of San Juan along 16 stations between Bayam„n, Guaynabo and San Juan. Loads of ferry services operate throughout the archipelago connecting the several islands of Puerto Rico. The state run ferries are fairly cheap. Another convenient way of getting around Puerto Rico is by renting a car or a moped. It is not very expensive when split between 2 or 3 people and the destinations are decently connected.