If you don't get a seat through the fee waiver category, you still have to pay full tuition fees that are 1.4 Lakhs in NIET Greater Noida. After that, you can apply for government-funded scholarships.
If you don't get a scholarship, remember that you can still apply for government-funded scholarships. Most will be for undergraduate students. The cost of tuition fees at most IITs is about 1.4 lakh per annum for a non-Reserved category.