来てるよ

has arrived

→ 来る
phrase Uncommon #19,748
has arrived A casual contraction of 来ているよ. Depending on context, it can mean someone or something is already here.
JA: 友達がもう来てるよ。
EN: My friend is already here.

来てるよ!

They’re here!

— 魔女の宅急便 (1989)

彩香ちゃんが来てるよ

Ayaka's here.

— When Marnie Was There (2014)

誰か玄関に来てるよ。

Someone’s at the door.

ナンシー、あなたに手紙が来てるよ。

Nancy, you've got a letter.

だれか玄関に来てるよ。

Someone's at the door.

電車が、来てるよ。

The train is coming.

また来てるよ

They’re here again.

— PERFECT BLUE (1998)

電車はもう来てるよ。

The train is already here.

列車は、もう来てるよ。

The train is already here.

ここは前にも来てるよ

I've been here before.

— ロード・オブ・ザ・リング/二つの塔 (2002)

二人とも来てるよ。

They're both here.