I had passed my class 12th exam in 2017 can I give both JEE Main 2019 January and April exam?
Yes you can give both the exams. Its upto you. No issues with that . All the best! Give your best and conceptually study the coarse and thoroughly so that you are successful . All the best!
Its not possible to have both the exam in the same corresponding year while you can try in upcoming year
JEE Main Sample Papers
JEE Main Previous Year Question Papers with Answer Key