Now only 10 days left for JEE advanced revise the concepts you learned, practice important questions if you have marked prior, practice previous years JEE advanced papers. For mathematics practice on topics like vectors, 3d,calculus, conic because these have a decent weightage in JEE advanced paper. For chemistry do have through revision especially salt analysis,for Physics focus on modern physics, electrostatics, electrodynamics,magnetism,EMI ,AC , rotation, thermodynamics . And also analyze the weightage of topics from recent jee advanced exams , also you should join some test series of reputed institutes but please don't go for any sort of crash course .