service provide to educational institute (kendriya vidalaya)

GST not applicable on security services provided to an educational institutions. Hence You have to generate the bill without GST.

Services provided -

a)    by an educational institution to its students, faculty and staff;
b)    to an educational institution, by way of,-
i.    transportation of students, faculty and staff;
ii.    catering, including any mid-day meals scheme sponsored by the Central Government, State Government or Union territory;
iii.    security or cleaning or house-keeping services performed in such educational institution;
iv.    services relating to admission to, or conduct of examination by, such institution; upto higher secondary:

Provided that nothing contained in entry (b) shall apply to an educational institution other than an institution providing services by way of pre-school education and education up to higher secondary school or equivalent.

GST = Nil

as per my information kendriya vidyalaya is central government school and provides education up to 10th or 12th standard then No need to raise GST bill.

so we have to mention GST notification number  on bill for exempted