Depends how days you want to travel because lots of places to visit in an around Gokarna Gokarna to Yana ( so beautiful place) Gokarna to Murudeshwar Lots of places to see around Gorkarna tell me how days I will suggest you
Plan for at least 4 days stay :
First day Enjoy at the beach of your choice and then go for beach Trek. Kudle- om beach- half moon - paradise beach.
On the second day go to Yana caves and Mirjan fort
Third day go to Murudeshwar
Last day explore Gokarna town and temples.
if you just want to be in Gokarna three days is enough