Answer by Professional Japanese Teacher
Koko ni imasu (yo).
Koko desu (yo).
The word for “here” in Japanese is ここ koko, which literally means “this place”.
You can use either of the above two expressions to say “I’m here”. “imasu” in the first expression indicates the existence of someone at a place. You can also add a “yo” at the end of the sentence to emphasize that you’re indeed at this location.
Other words related to location are そこ soko (there) and あそこ asoko (over there).