You will be expected to map your way. You’ll be expected to use your map to find your way out and around.
However, you do not need to be exact! Make an effort to be vaguely accurate and I’ll consider it good enough and won’t try to screw you because you didn’t draw a corridor just right or accidentally overlapped a couple rooms.
Also, player knowledge is accepted. If the map fails, but a player can remember, “No, we went about 100 feet then turned left, took the second door, and took the left fork,” that’s good enough for me.
In cases of map-related confusion, I will almost always rule in favor of the players — the PCs are actually experiencing the dungeon and their mapping and memory are superior to my verbal communication of the environment.
Also note, though, that there will be times in which there is intentional confusion, changes, problems in mapping and finding your way!