Hello aspirant.

To become eligible you must have passed class XII or qualifying exam in 2017 or 2018,or  appearing in class XII or equivalent qualifying exam in 2019 can also apply for JEE Main.

Minimum score that you need to score in exam is as follows (As you have not mentioned which board and maximum marks it is not possible to tell whether you are eligible or not , please see down you will come to know )

75% marks in class XII or equivalent exam or be in the top 20 percentile in their class XII exam conducted by the respective board.

For SC/ ST candidates, the eligibility criteria are to secure 65% marks in class XII or equivalent exam.

For more information refer 

https://www.google.com/amp/s/engineering.careers360.com/articles/jee-main-eligibility-criteria/amp