I got 52 percentile in jee main 2019 I am from obc category, did I qualified or not? and how Mark's I got ?

Hello aspirant,
No, you haven't qualify JEE Mains. The cutoff for OBC is 78.2174869%ile...

Hello dear
No you are not qualified for jee advanced because cut off for obc category student is 74.3166557.
And you secure less than this ; talking about marks we can not calculate marks from the percentile score because percentile is a relative score depend upon the number of students who score more than you and total number of students .
Like :
Even if you score 200 or 250 but in both case number of students who score more than you is same than your percentile remains same ( so percentile is not depend upon your marks but on other students also.).