Learn Turkish: Anahtar burada.

Turkish does not have a direct word for 'the'. Anahtar can mean 'a key' or 'the key' depending on context. Because we are pointing out where a specific key is, 'the key' is the natural English translation.

Where is the word for 'is' in Anahtar burada?

There isn't one! In Turkish, simple statements about what or where something is (like 'it is here') often do not need a verb. Just placing the subject (anahtar) next to the location (burada) is enough to mean 'The key is here'.

If the lesson is about nerede (where), how would I use it with this sentence?

This sentence is exactly how you would answer the question Anahtar nerede? (Where is the key?). Notice how both the question word nerede and the answer burada share a similar ending. The location suffix -de or -da means in, at, or on.

The word for 'this' is bu. Where does the rest of burada come from?

To talk about a location, bu (this) changes to bura (this place). Then we add the location ending -da (at/in) to make burada, which literally translates to 'at this place' or 'here'.