Hey Joshika,

For appearing in assam cee exam a candidate must be a domicile of Assam.must have passed there 12th standard with PCM. 50% aggregate collectively in Physics, chemistry and maths. So of you're pass in your physics subject then you are eligible. In most cases 33% atleast is considered as pass.an a student must have to be pass in Theory and practical as well in CBSE. Maybe your board might have different criteria. 

Eligiblity criteria full detail below

engineering.careers360.com/articles/assam-cee-eligibility-criteria/amp

Best of luck