Hello aspirant

According to the NEET 2021 Tamil Nadu rank list, a candidate scoring 450 marks had a state rank of around 8271. This year, considering the paper difficulty level, you can expect your rank to be around 8350-8500. Hence getting a seat in a government college will be difficult, considering you belong to the general category.
At this score, you will be able to get a seat in the following private colleges. I am also mentioning their mop up round cut off marks-

Indira Medical College, Thiruvallur- 413

Annapoorna Medical College, Salem- 420

Dhanlakshmi Srinivasan Medical College- 440

You can also get deemed medical colleges at this score. However, please note that cut off changes every year depending on various factors such as category of the student, difficulty level of the exam, number of students attempting the paper etc.

To predict the colleges you can get into, you can use the NEET 2022 College Predictor tool- https://medicine.careers360.com/neet-college-predictor

Hope it helps!