Hi Helen! To "be on the same page" as someone means that you understand each other and there is no miscommunication between you. For example: "I want to make sure that we're on the same page, you will do the research and I will do the report, right?" "I don't think we're on the same page about the schedule. I will come in at noon instead of nine o'clock, ok?" I hope this helps!

When everyone agrees with the same thing or same level... Ex: "We are understanding each other".

Another commom equivalent would be ' singing from the same hymn sheet' if you fancy anorher one to put in your locker!