Why the pressure of atmosphere doesn't cruch you when eq. walk outside?

for the same reason that a fish doesn't notice the pressure of the water.

We're used to it, and adapted for it.

The same pressure pushes up against us, and in from the sides, and fills our lungs.

It's when the pressure is taken away that we experience problems.

So stay in the house.

1 Atm pressure at sea level is 14.7 psi (lb/in^2), 760 torr, 1000 millibars, 760 mm Hg, 29.8 in Hg, 101.3 Kpa, or about 32 feet water column. Everything in your body except your lungs, sinuses, and ears are filled with liquids which are incompressible fluids or solids. Your lungs, sinuses, and ears are filled with air, a gas--a compressible fluid--when you go up or down in elevation you will exhale or inhale equilizing pressure in your lungs. Your ears and sinuses may get painful if you don't yawn or pop your ears to equalize pressure.

IOW everything inside your body is in a pressure equilibrium with the atmosphere outside of your body--that is unless you do something unusual--like water dive to great depth (greater than about 200 atm pressure) or expose your body to extreme vacuum. The good news is that with vacuum you'll probably lose consciouness because of lack of oxygen well before you die.

Rap

But for God's sake, don't try to hold your breath...