Koh Samui is an island so the only way to reach is by boat or flight.
Major cities in India are connected to Koh Samui although the flights are very expensive. It is a better option to go to Bangkok and then take a bus to SuratThani and a ferry from there to Koh Samui. If budget is not a constraint you can consider one of many flights flying to and from Kho Samui connecting to different Indian cities.
Smae visa policy is applicable for Kho Samui as for any other Thai city. Visa on arrival is applicable on Indian tourists. All information is provided on the official embassy website.
Koh Samui has the privately owned Samui International Airport. Flights can be taken from major cities to the airport. More expensive option than reaching by Ferry, it is not one preferred by budget travellers or backpackers.
Motorbikes and cars on rent are the preferred option for tourists on this island. News-gathering run for short distances if you wish to use public transport. Taxis run on the island if you don't mind a slightly more expensive but convenient affair.
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