I'll be dividing this answer into 4 parts depending upon the year.

1st Year

1. Hostel Fees : 25000/Semseter for a 4 Sharing Room, 28000/Semseter twin Sharing with AC.
2. Tuition Fees : 75000/Semseter
3. Admission Fees: 11000 (One Time)
4. Alumni Fees: 1000 (One Time)
5. Examination Fees: 2000/Semseter
6. Medical Fees: 400/Semseter

Mess fees are around 2800/Month. College operates for 10 months, so 28000 INR.

Total fees for First Year comes around to be : 330,000 INR.

2nd Year

Everything remains the same and with the changed hostel, the fees for Hostel rises from 25000 to 40000 / Semseter.

Tuition Fees Increases.

Mess fees would rise from 2800–3000 INR.

A total of 360,000 INR would be needed for 2nd year.

3rd Year & 4th Year has almost the same fee structure as of 2nd Year.

Total cost of studying at Thapar including the mess fees is around 15–16 Lacs.

Atop this, your expenditures are in your own hand.