Can't comment on eating or drinking I'm afraid, I usually stick to trackside food.
You'll find that in Zandvoort, pretty much anywhere is a good vantage point. The track is set in sand dunes, some feel like they tower above the track. Plenty of spaces where you can get a clear view free from fences.
Whatever you are seeing, make sure you go for the full weekend. The whole track is worth exploring. Turn 1 (Tarzan) was my choice for the DTM race day a few years ago:
There was another huge dune in the middle of the track that let you have a clear shot of this chicane:
One of my favourite tracks that I've visited. I'm sure you'll love it! What race are you seeing?