Flight related query. Please if anyone can answer.

I'm booking tickets for a flight to my destination, but it involves a layover at an intermediate airport for 30 minutes. If I book the full journey as a single connecting flight, it costs ₹7,500. However, if I book the two legs of the journey separately on the same airline, the total comes to 5,100-significantly cheaper. My concern is about the layover. Since it's the same airline, will they allow me to stay onboard during the stop at the intermediate airport, or will I need to deboard, go through the check-in process again, and then reboard within that short 30-minute window? Should I go for the cheaper, separate bookings or pay extra for the security of a single connecting ticket