No, you are not eligible for SBI clerk 2021 because according to eligibility criteria candidates who were born after January 2, 1993,and before January 1, 2000 can only be eligible for the exam. So you have got plenty of time to prepare for this exam. I hope this may help you.
Age limit for SBI clerk exam is candidate should be a minimum of 20 years and maximum of 28 years.
Therefore, candidate should have not born before January 02/01/1992 and not later than 01/01/2000.
Your dob is 16/08/2000 so you can eligible for SBI clerk 2021 exam.
Here is the link for SBI clerk 2020 information on careers 360 .From this link you get more information about exam.
All the best!