can he apply for TNEA as a normal candidate

Hey Sundar,
The eligibility criteria of TNEA 2019 are a set of conditions related to nativity, age, qualifying exam, etc. that each candidate needs to meet in order to be considered for admission. In such cases where the candidate doesnt meet the prescribed TNEA 2019 eligibility criteria but still applies for admission, their applications wont be considered.
As you know better about yourself like domicile, caste category or any special quota. So I am hereby providing you the career360 link so that you can know the eligibilty criteria of the examination.

https://www.google.com/amp/s/engineering.careers360.com/articles/tnea

I hope this will help you out, for further query you can comment below without any hesitation.

All the best.