"There is a delicious pizza on the table."
Translation:На столе вкусная пицца.
I don’t think putting «е́сть» at the beginning of the sentence sounds natural. If you want to use «есть», it’s better to put it before «вку́сная пи́цца»: «На столе́ есть вку́сная пи́цца».
The default question would be «На столе́ есть вку́сная пи́цца?». But you’d have the question particle «ли», you need to move «есть» to the beginning: «Есть ли на столе́ вку́сная пи́цца?».
Also, you can move «есть» to the beginning of the sentence if it’s emphasised by the intonation: «Есть на столе́ вку́сная пи́цца.» This sounds like an answer to someone who claims there's no tasty pizza.
I enter that term into the context search at reverso.net, which cited a number of Russian sentences indicated that it is a way of saying "(there is) located" or "[a thing] is located at" [a particular place]. На столе is just a simple way of saing something "is on the table", without getting into the precision of saying saying "is located" in a particular place.
Have a look at some of the sentences I saw at http://context.reverso.net/translation/russian-english/%D0%BD%D0%B0%D1%85%D0%BE%D0%B4%D0%B8%D1%82%D1%81%D1%8F
I use context searches frequently to try to get a feel for the way words are used, even if I don't understand much of what's being said exactly - just enough to get a vague idea of why the phrase is not particularly useful for the exercise, evcen though it is relevant in some ways.