Exchange rate (forex) is improving every day.But,cost of living is increasing ,percapita is going down ,why?

Our economy is not based on Imports & Foreign countries. Then how one can, compare Cost of Living, by FOREX?

Forex improving ? ; you mean devaluation of Rupee compared to Dollars , Euros and Pounds or Vice-Versa ? Per Capita is in fact increasing . But yes for Common people in India COst of Living is increasing due to Rising Petro Prices, Rise in prices of Vegetables and Fruits and other Items too. Some points that can help out of this :
1: Agricultural Reforms : Veg and Fruits Price Rise don't help Consumers and Farmers . They only help Middlemen . Provide more opportunities to Farmers to Directly Sell to End Consumers . Get more FDI into Cold Storage Chains etc.
2: Increase Use of Renewable sources of Energy and reduce Consumption of Petrol and Diesel by adopting more Fuel Efficient Means iof Transport, car Pools etc .
3: Industries should invest more to cut Pollution.
4: Government should cut size ; corruption has and I repeat has to go down for a Better India .
Full Stop

Inflation can only come down if Fuel import Bill can be checked.

Today one good news is that use of 5% ethanol in Petrol has been given a go ahead, which will somehow check the Fuel bill. Actually, Petroleum products make every goods / service expensive due to Freight charges rise. Hence the cost of living is rising.

Others is the rise in the interest rates by RBI which it seems wants less cash flow in the Banks by increasing the interest rates!!!!!!! (Demand and supply of money ).