This purely depends on what course are you searching for .If you want good engineering colleges than your percentage should be above 85%in 12th standard.
For colleges other than engineering your percentage matters a lot but that's not the only thing that matters .
Along with that your category that is ( SC , ST ,GENERAL , SEBC ) also plays a major role . approximately you need above 80% and marks in your class 12th to get a college in chandigarh in the first round of pmsss counselling itself .
You can read the related answers here :-
https://pmsss.in/137/punjab-engineering-college-chandigarh?show=137#q137
https://pmsss.in/295/i-got-319-marks-in-class-12th-can-i-get-cse-branch?show=300#c300
