This is the 5129th most frequent Russian word.
напитком
A drink or beverage.
In this sentence, 'напитком' is used in instrumental case as it describes the means of enjoying.
Я наслаждаюсь этим прохладным напитком.
I am enjoying this refreshing beverage.
Here, 'напитком' is transformed into its nominative case 'напиток' to denote the subject.
На вечеринке нам предложили попробовать новый напиток.
At the party, we were offered to try a new drink.
In this example, 'напитком' is in the genitive case 'напитка', indicating possession or association in the context of the choice.