Let's look at each of your sample sentences in turn.
Breaking this down word for word:
eating-thing → food
deliciousness (as a degree or amount)
[copula]: is, are
Putting this together:
Is food [a degree of] deliciousness?
That doesn't make a lot of sense, ...
Let's look at your sentences and explore their meaning.
This says, "Is the food tastiness?" I don't think that's what you want to say.
This could possibly work, but it still sounds a bit off to me. (But, I'm not a native speaker.) What strikes me odd here is the use of the particle が. Had you written it as
乗る on its own only describes the action of mounting or boarding itself. The "destination" marked by に must be a vehicle (or a boat, a horse, etc), not some geographical location. 東京に乗る or 仕事に乗る does not make sense (although "to ride to Tokyo" is a valid expression in English). 車に乗る does not necessary mean you travel to somewhere; you may ...