Don't know much about the place.  If it is a resort they may have resort
courses available.  This would at least give you a feel for scuba.  They
tend to be expensive, and the diving very costly for what you get.  If
you are comfortable in the water, snorkelling is fairly simple.  Just
remember to breathe in and out of the snorkel (but not underwater)!

Ther may be some here who are familiar with the area.

Try the link below.  Select options to see what they offer.  You will find
something.
http://www.101scubadiving.com/directory/hurghadadivingcenters.html

Hi,
You should post your questions on uk.rec.scuba, the UK being closer to
Egypt then the US, more people on that NG will be able to give advice.
Your hotel should be able to arrange an intro dive and an Open Water
course. Unfortunately Hurghada has been overdived (ISTR a figure of
1200 dive/snorkelling boats operating around HRG) resulting in a lot
of damage to the reefs.
As to your question about marine life to avoid, basically just look,
don't touch especially the cone shells, lion fish and stone fish (i.e.
what doesn't move or moves very slowly). The rest will get out of your
way before you see them :-)
If you are snorkelling wear a T-shirt.
HTH
John