Hi shashirranjan, and welcome to AF.
Can you provide us with a bit more information, so that we can better advise you? What phone you have, whether the problem is with mobile internet or with WiFi also, whether you can make other internet connections or the problem is just with Google Play?
One generic thing you could try is clearing data for the google Play Store app, which might help if the problem is with Play only and not internet connections in general.