I had mentioned the destination at Toronto in my application.But now i want to go at Calgary. Is this change of destianation possible?

Sure you can land anywhere in Canada with the exception of Quebec province. We had given destination of Windsor, ON but landed in Winnipeg, MB.

After landing you can settle anywhere in Canada including Quebec.

Note: If you are a provinical nominee you need to complete residency requirements of your province. If you applied for skilled worker immigration under the federal immigration programme, then my reply above holds.