The biggest threats to productivity are various distractions and time wasting tasks that come from other people.
Whenever possible, use email and other messaging systems that are asynchronous.
This reduces interruptions.
Turn off notifications.
If there is something important, people will call. You don’t need notifications on your mobile phone and laptop.
Unless the meeting is really important and has a clear agenda, it is a waste of time to attend.
A noisy office can be very distracting.