Hello Pinky,

You can opt any of certificate courses, diploma courses or Bachelors degree courses in Graphic Designing. All of the colleges mentioned below provide a merit based entry system. The top colleges offering courses in Graphic Designing in Chennai are

ICAT design and media college (Bachelors degree in Graphic Designing) - merit based entry

Loyola college, Chennai (Diploma)

Madras Christian college (Certification course)

Vels institute of science, technology and advanced studies (Graduate diploma)

Institute of design ( IOD) (Graduate diploma)

DOT School of design (B.des)

You can find further information about the course in the link provided below

https://design.careers360.com/colleges/list-of-graphic-designing-colleges-in-chennai

Hope this helps and Good luck