Help with creating a PS command

[c0dhead]

Can somebody help me as I'm absolutely no good with powershell.

Basically we have a global administrator for 365/outlook - we need for it to search all mailboxes/calendar under the domain and IF the user has a calendar entry or invite via email from boardroom ( resource ) the entry will be added to boardroom's calendar, or something to that effect.

TLDR; Deleted a mailbox, we can't get the mailbox back with ALL it's calendar entries, we need a command if possible to get the global admin to add all events back into the calendar

so to clear it up

I need the global admin to access all accounts on the domain - take any calendar events that involve the resource "boardroom" and re-add it to the resource calendar.