“I don’t know”.
Give up the need to have all the answers.
You can consider this your official permission slip. Print it off and stick it on your desk.
Not only is it okay it’s actually generous to those around you (especially if in a position of power). It humanises you, shows others it’s okay to not know and provides an opportunity for someone who does know to shine their light.
And yes, turns out there probably is someone who knows something you don’t.
The opposite is to pretend you know all of the answers to just about everything, and we all know how that ends.