"Wine is not a meal."

Translation: Wino nie jest posiłkiem.

[juanalcat]

Can it be Wino nie jest obiadem?

[4d1n]

Not, "obiad" means dinner. "Posiłek" is used while you're thinking about breakfast/lunch/dinner/supper, but don't precise it.

[silmeth]

Could be wino nie jest posiłkiem, but not obiadem when translating English ‘meal’.

[victor.pacanza]

I put 'Nie wino jest posiłkiem', why is this wrong?

[Jellei]

That's like "It is not wine that is a meal".

You tried negatine "wine", you should negate "being a meal".