go to an emtek dealer and ask

Double cylinder means you need a key to open from the inside. IMO, this is a fire risk as you can get trapped in your home. Single cylinder means there's a latch on the inside. Some companies make a captive thumbturn option that has a removable latch in case you go on vacation.

As for the handing of your door, this is what Baldwin says for their handlesets:

"Determining the handing of a door is simple; facing the door from the outside of the room or home, locate the location of the door hinges. If the hinges are on the right, it is a right-hand door. If the hinges are on the left, it is a left-hand door."