Actually the context is a bit slim for a substantial answer.
As answer to a question like: "What would you like to drink, orange juice, beer or a glas of wine?" gern(e) (not meant as one-word answer but e.g. within "Ich nehme gern einen Wein") simply states preference for the latter with conotation of some politeness. (This seems the meaning @Twinfriends addressed, but is far from being the only one.)
As a stand-alone statement it could express a habit, similar to
Ich mache abends gern einen Spaziergang. (I like to take a walk in the evening)
(obviously one also has to like doing this, otherwise one would not do it so often) or, more similar to you example and also more tending towards peference
Ich trinke gern einen Wein zum Fisch.
I like to drink a glas of wine, when having a fish.