Yes, it is similar to the word youth in English in that can be used to describe an individual or the general generation of young people. Though I think in English we would tend to say 'young person' and not 'youth' in a lot of places.
I would argue 'Youth eats out' is quite a poor translation and perhaps should be removed. That sentence is quite confusing to a native english speaker and sounds very wrong.
Ok, so I am a bit confused...what does νεολαία mean exactly? Is it a "young person" or is it "young people" (or both)? The translation given above- "Youth eats out" (which by the way, sounds a bit odd in English) seems to suggest the latter meaning, but I am not sure...
I am thinking that the plural: Young people eat out is something like "Νέοι άνθρωποι τρώνε έξω." And that the Duo sentence is singular -- one person only -- but I await to be corrected by anyone who is a genuine Greekophone. Edit: I consulted another dictionary which says that H νεολαία can refer to young people as a group.