Hello Aspirant,
Bachelor of science in geography is provided by mamy colleges in Chennai, Tamil Nadu. Some of the best in Chennai are:

• Madras Christian College
• Presidency College
• Queen Mary's College
• Madras University Distance Education
• Ramakrishna Mission Vivekanand College

and some of good college around Tamil Nadu are

• AVVM Sri Pushpan College
• Periyar EVR College
• Tamil Nadu open University.

AND MANY MORE.
The basic eligibility criteria to get admission in these college is that you should have passed your 10+2 with minimum  50% from a renowned board. The annual fees of these colleges may vary from 5000 to 20000 or even 25000 in some colleges.
Bachelor of Science in Geography is a 3 year graduation course after which you can get good jobs with starting salary varying from 15000 to 30000 depending upon the placements in your college . To get more information about these college you can visit the official website.
Hope that answers your question.
Thank you