Bottle with some fluid

I want to create that bottle with some wine or oil inside. Shape of the bottle is not a problem. More diffucult is put into the liquid. I don’ t know what way would be better - by simulation or just moddeling, and how I can achieve one of these solution. Also you can show me some tut on YT, but I didn’t find anything helpful.

If the liquid is not moving around, splashing, etc, there is little point in using the simulator. Just model the shape of the still liquid inside the bottle.