FOR B TECH ADMISSION WE HAVE TO UPLOAD COPIES OF CERTIFICATES ALSO DURING FILLING ONLINE APPLICATION
Could you possibly elaborate on which 'certificates' are you referring to, here?
However, while filling up the form of B. Tech. or during counselling you will not be required to upload copies of any certificates of any curricular or co-curricular activities. Instead, your previous mark sheets would be mandatory.
Hope this helps. Good luck!