のは初めてです

it's my first time

→ の
phrase Rare #25,169
it's my first time Used after a verb in its plain form to say that doing something is a first-time experience. In questions, it means “is this your first time...?”
JA: この料理を作るのは初めてです。
EN: It's my first time making this dish.

を見るのは初めてです

This is my first time seeing snow.

この症状が出たのは初めてです

Is this the first time you've experienced these symptoms?

聖書を読むのは初めてです

This is my first time reading the Bible.

この町へ来たのは初めてです

Is this your first time coming to this town?

韓国に来るのは初めてです

Is this your first time in Korea?

アラブ書いたのは初めてです

This is my first time writing in Arabic.

日本に来たのは初めてです

Is this your first time in Japan?

森の中に車を停めるのは初めてです

This is my first time parking a car in the woods.