Hello Aditya,

If you are applying for Anna University, Chennai; then the minimum marks that you should be considered to be on a safe side is 70 plus percentile, because it's a great University, and many students apply. So it would be a competition.

Still, if you want there is a detailed answer on our website blog for Anna University. Please do check it::

https://engineering.careers360.com/articles/tnea-cutoff 

and All the best for Boards !!