How much percentile should i get in 3 different sections to qualify in CAT exam

Dear Shaik, you haven't mentioned your Category. Neverthless, the CAT sectional weightage depends on your target College. For example, this is how it looks like for few IIMs for each Category:
IIM Ahmedabad:
QA        DLR      VARC       Overall
General:                            70           70           70             80
NC-OBC/Trans:               65           65           65             75
SC:                                     60           60           60             70
ST:                                     50           50           50             60
PwD-UR,OBC,SC:           60           60           60             70
PwD: ST:                          50           50           50             60

IIM BANGALORE:
QA          DLR        VARC        Overall
General:                           80             80            85               90
NC-OBC:                          70             70            75               80
SC:                                    65             65            70               75
ST:                                    60             60            60               70
PwD:                                50             50            50               60

IIM CALCUTTA:
QA             DLR         VRC        Over All
OPEN:                             75               80            80              85
NC-OBC:                          65              65           70               75
EWS:                                65              65           70               75
SC:                                   60              60           65               70
ST:                                   55             55            55               65
PWD:                               55             55            55              65

FMS DELHI:

QA: 30%
DILR: 30%
VARC: 40%

IIM INDORE:

QA          DLR        VARC       Overal
General                 80             80            80             90
NC-OBC                70             70            70             80
SC                          55            55            55              60
ST                          45            45            45              50
PwD                      45             45           45              50

IIM LUCKNOW:

QA            DLR         VARC        Overall
General                85               85              85              90
NC-OBC               77                77             77              82
SC                         55                55             55              70
ST                         50                50             50               65
PwD                     50                50             50               65

Hi,

There is a sectional cut-off in CAT which you have to qualify as well as the overall cutoff. As per the 2018 results, in order to get into IIMs you will need to score above 70 in each section if you are from general, 65 for NC-OBC, 60 for SC and 50 for ST, 60 for DA and 50 PwD.