Outlook Online has a Snooze function, just like Gmail. Use it to move items out of your inbox until you’re ready to deal with them and stop your inbox from filling up with emails you don’t need right now.
Gmail’s Snooze option was one of those new functions that was so obvious in hindsight that you wonder why no one did it sooner. You select an email, choose a snooze time, and it disappears out of your inbox, only to reappear as if by magic at the required time. Brilliant!