It is also believed that we can go through walls (i know, wtf), but it has such a small chance, that we will probably need to simply push the wall for the rest of our lives to experience it.
This isn't true at all.
? That's what I have heard for string theory/ quantum physics O.o
Help me a little?
Quantum physics really doesn't say this. The idea came from the theory of quantum tunneling. That's a real phenomenon in which waves and wave-like particles can bypass certain barriers under special conditions. Parts of your computer are based on this principle and even certain proteins in your body use quantum tunneling to catalyze chemical reactions.
But you could never actually use quantum tunneling to move through a wall.
From a physical standpoint, and to the best of my knowledge, the distance that a particle can tunnel must be extremely narrow and the conditions must be very specific. Walls are neither extremely narrow nor do they fit the conditions required for quantum tunneling. Compounding the problem is the fact that all of the particles in your body are under completely different conditions at any one time -- there will never be a time in which they all hit an appropriately narrow barrier under those specific conditions at the same time. Thus, this could never happen.
From a statistical standpoint, it would require that every single particle in your body tunnel the exact same distance in the exact same direction at the exact same time (ignoring the requirements I wrote about previously). Though there is some infinitesimally small chance of this happening, it never actually will. This small possibility is probably what got people believing the myth in the first place, but again, the conditions will never be met physically.
These theories describe the behavior of quantum particles, not macroscopic objects like people and walls.