Hi,

For preparation NCERT is enough to get you a good rank to fetch your desired streams but again the marking scheme is relative and VIT doesn't disclose the actual score you get. All that what they give is rank which is very controversial amongst aspirants.

You can prepare with Class 11th & 12th NCERT and practice from mocks of Arihant Publication and Disha Publication. In the last month you can practice for past 10 years VITEEE questions. Aim to get a rank around 5k then only you can get CSE in category 1 tuition fees at Vellore Campus.