Sir,
Advance tax is applicable only to the assessee if tax amount is greater than 10,000 and it is not applicable to senior citizens if they have income other than pgbp.
calculation-is based on your previous return .If you didn't fill your up to now then you will provide the details .
1. sources of income
2. amount of income
3. person-individual,firm,...
4. Age , chapter VI A deductions in case of an individual
5. TDS if any