How do you get to the temple in lake hylia?

I don't know what game you are talking about but if you mean Ocarina of Time you need zora tunic and the iron boots to walk into the temple and not drown. Then use the hookshot to pull the switch at the top and open the door. If you mean Twilight Princess you need the zora armor to dive to the to the bottom of lake hylia where the temple is. Put on the iron boots and use a water bomb to break rocks on a jet. Then put another bomb ao the jet to break the rock in the way to get in the temple. With the rock destroyed you can get in.