1, The stars we see in the night sky are very far away from u, so far the atar light we see has taken a long time to travel across space to reach our eyes. Vegas, the bright star we see is relatively close to us at 25 light years away. The light we see left the stars 25 years ago. (Lifehack)
The ocean looks blue because red, orange and yellow(long wavelength light) are absorbed more strongly by water tahn is blue(short wavelenght light) So, when white kight from the sun enters the ocean, it's mostly the blue that gets returned, Same reason the sky is blue (Google) Watch video above.