その1 to go to an event, place, etc.: 場所やイベントに行く Over two hundred people attended the funeral. The meeting is on the fifth and we’re hoping everyone will attend.
その2 to give attention to what someone is saying: 誰かの発言に注目する I’m afraid I wasn’t attending to what was being said.
その3 to provide a service to someone, especially as part of your job: 仕事の一環として誰かにサービスを提供すること The queen was attended by her ladies-in-waiting. 女王様は侍女に付き添われていた
職場でよく目にする attend + to
attend to で引けば辞書に出てきますが、私が職場で出席以外の意味でよく見かける attend はこれです
I am off today. Let me attend to your email upon my return.
本日は不在にしております。戻り次第お返事いたします。
So, in this case, “attend” is more about addressing or handling the email rather than providing a service or merely paying attention. It implies that you will get to the email and take the necessary actions or reply to it when you return.