How do you put liquid in a bottle?

I was wondering if it is possible to have a liquid inside a bottle and it moves depending on how the bottle is positioned in 3D. It doesn’t have to be anything complicated and realistic. Like when you tilt a bottle the liquid evens out becoming parallel with the floor like this image:

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I ask because I was just playing The Last Of Us and there was a scene with a bottle and the liquid moved around and I was wondering if that is possible in Unity.

Maybe this will help.