No, you do not have to pay an entry fee to enter the Gokarna Mahadev Temple in Gokarna.Â
The Gokarna Mahadev Temple was built in 1582. Most of the sculptures here are related to the Hindu Gods and Goddesses. The sculptures here depict gods like Aditya (Sun god), Chandra (Moon god), Indra (the god on an elephant) and Ganga (the goddess with a pot on her head)
You can take photographs of the temple. However, it is always better to ask permission from the temple guardians before taking photographs.