how do u go through walls

[theiving bullet]

ok ive been trying to find out how to go through wallls so that i can go around the middle of below the map and also gothrough the walls including the floor but when u get on the ground u can walk on the floor like normal and in certan places or somehow go through the floor

[NoiseTank]

turn max helth max overshields damage resistance and less damage
then use something to cause a big force and youl go through the wall with just enough helth to survive


i have tested and used this glich many times

[M9 HE-DP Grenade]

hey i just got an idea to make a mod where u play as a ghost o_0