I'm going to buy used Nikon AF-s 105mm f/2.8 from Adorama?

I live in india, and I'm thinking of buying Nikon 105mm lens in Adorama. So if I buy there they charge me for shipping USPS $55 or FedEx $77.So does these charges include customs, import duty and all…

Read the fine print: likely not, which means you're responsible for those fees.

No, it's not included. You have to deal with the tax and duty in your own country. Sometime, they will charge you the broker fee. So it could end up not worth for buying it oversea.