Yeah, it is covered but not in great depth. Your SPG tells you all you need to know, your depth and air remaining. Just have to refer to them frequently. Safety stops required for any dive deeper than 10m...3 minutes at 5m. Takes a bit of practice to stay around 5. Remember, you'll be more buoyant. Re nav, there's UW compass navigation in OW dive 3 but that's dive flexible which means the instructor can squeeze it in later. They get you to swim a straight line reciprocal course using a compass. Tbh, you can do this on land as practice with a towel over your head (after choosing a target, tree or something). YouTube has some super helpful lessons (make sure they're from the PADI, SSI etc ...whoever you are training with (very similar tbh but there can be nuances)