Dear Divya, kindly refer to your LTA (Leave Travel Allowance) policy. You can get LTA only if you have applied for leave from your company and have actually traveled. However, international travel is not valid. Only the travel costs are covered. So, whether you fly, hop on a train, or take public transport, you will have to show the ticket to claim your LTA.
LTA covers travel for yourself and your family. Family, in this case, includes yourself, parents, siblings dependent on you, spouse (even if your spouse is working), and children. You can claim the LTA benefit just once in a year. If you switch jobs, you can get the LTA not only from your present organization but also from your former employer if the concession is lying unutilized.
You must take the shortest route to your destination to be eligible for LTA. If your LTA is not utilized, it gets added to your salary, and you will be taxed on it. Hope this may clear your query.