I am a first time traveler and I've been refused boarding on a flight to India due to lack of needed documents. Now I have the documents from my sponsor in India. He bought me a ticket on MakeMyTrip. From the Philippines, I will go via Singapore to fly to India. What is the process? Will Philippines Immigration ask me lot of questions?
First, you must be sure that your sponsor is legitimate. The Philippine government put that process in place because a lot of pinoys have been tricked into slavery or prostitution in foreign countries by sponsors who appear to be trustworthy.
If your sponsor is someone you know well and who has visited you in Philippines, then you should know enough about them and about your trip to be able to answer questions that immigration staff ask you. Even then, there is a risk that this is a scam.
Allow plenty of time at the airport so you don't miss your flight.