What kind of chemical I should use to clean a swimming pool in india.
Please refer me a cost also.

I assume you mean keeping the pool clear of algae and bacteria.

I believe the least costly material is hypochlorite, either calcium hypochlorite (70% chlorine) or sodium hypochlorite available in various concentrations. Either of these materials should be generally available at a reasonable cost. The Calcium hypochlorite is a solid and would need to be dissolved in water and the precipate allowed to settle out before use.