Upvote:1
As your itinerary takes you through Singapore on both legs of your journey, you would need to apply for an entry visa, and its validity determined by the itinerary you present upon application (for your onward and return). Booking two round trips tickets, India-Singapore and, separately, Singapore-Vietnam, creates a layover or stopover.
You mention breaking your journey; you don't say how, whether it would be for just long enough to take the next flight, a layover of a matter of hours, or a few days, a stopover. Either way, you would not be able to take advantage of Singaporeβs Visa Free Transit Facility,
FOR INDIAN NATIONALS
Indian nationals are required to apply for visa to enter Singapore. Indian nationals holding official and diplomatic passports are exempted from the entry visa requirement. For other nationals, to find out if you require a visa to enter Singapore, you can contact the High Commission or visit the Immigration & Checkpoints Authority of Singapore website at www.ica.gov.sg
Travellers at Singapore Changi Airport who are in transit and who are not seeking entry into Singapore, do not need to apply for a visa if they remain in the transit area.