This is the 657th most frequent German word.
gern
"Gladly," "with pleasure," or "enjoying."
Here, 'gern' expresses the subject's enjoyment or liking of playing the guitar.
Ich spiele gern Gitarre.
I like to play guitar.
In this sentence, 'gern' indicates preference or inclination toward eating Italian food.
Er isst gern italienisches Essen.
He likes eating Italian food.
'Gern' in this example conveys the joy or pleasure associated with traveling to the mountains.