"Where are the young cooks?"

Translation: Hol vannak a fiatal szakácsok?

[scoobyroo]

Is vannak necessary here?

[Findil]

Yes, it is. It's left out only when the structure is:

noun = noun: Ezek a férfiak szakácsok.

pronoun = noun (or the other way around): Ők szakácsok.

pronoun/noun = adjective: A szakácsok fiatalok.

[Luzibr]

When adjectives go to plural? When not?

[VinnHoward1]

Music artists who sing at concerts post coVideo...the #NationalHymns in every language...

<h1>HimNosNatSionAlles</h1>

https://youtu.be/FHNLdHe8uxY

[sImQfWat]

Should "Hol a fiatal szakácsok vannak?" be accepted?

[jzsuzsi]

No. Wrong word order.

Keep hol+vannak next to each other.