Is there any lens filter or any other technique, that I can use to photograph lakes, oceans or any water source, without the reflections on it?
Every photo of a water source can be seen with a reflection of any objects or the reflection of sky. I just need to capture the lake without any reflections on water.
What is the technique?
A polarizing filter will do the trick for you. It removes the reflections you mentioned.
Browse online for examples.