Hello 

Greetings

Your percentile is 78.769 It means 78.769% student of the Total student appeared for the Exam are Behind You Therefore 21.311% students of the Total students appeared for the exam are Ahead of You, Therefore Your calculated Approximate rank is 186358

 But Note that This is Not Your Final Rank Your Rank may change Because It depends on Performance of You and Others in the JEE Main April, And the final Rank would be calculated Based on comparing Final percentile ( Whichever is Higher in Both the attempts if any) of all the students

As per Your current Performance, You may be eligible for JEE Advance But the final cut off will be released once the JEE Main April gets Over

Hope this Helps All the Best