If the centre of the Earth is incredibly hot then why is the bottom of the ocean cold

They're hiding this from you if the centre of the Earth is incredibly hot then why is the bottom of the ocean cold? It seems strange that the temperature of the ocean above the Earth core is so cold when we're told there's a massive heat source beneath us how can the Earth core be so hot if the water right above it is near freezing scientist, save the centre of the Earth is like a fireball but the deepest part of the ocean is cold enough to kill a person in minutes but this is what it gets scary. If the deepest anyone has ever drilled into the Earth is only about 12 km. No one has gone deeper that's less than 0.2% of the Earth radius and if we've been lied to from the start, maybe there's more to the Earth and we're told I believe Antarctica isn't just a frozen desert. They say it's a massive wall of ice spilled to keep us out or to keep something in old maps made by forgotten explorers show continent that don't exist today hidden lands entire world that were erased from modern history. What if these hidden lands are home to ancient beings, mysterious creatures we've never seen or civilizations with technology so advanced it would make our look primitive comment earth and I'll send you an image of what they're really hiding in Antarctica.