Ender4576 just follow the signs for Transfer. If you have your onward boarding passes then go through security and into the airside departure area. There is no passport control for transfer. The Airport hotel and lounges are all airside.
A word of warning: the airport hotel, which is airside, is usually fully booked a long time in advance. So unless you already have a confirmed reservation you are unlikely to get a room.
You give no information as to flight numbers, cabin class or OW status so my reply must be as vague as your question.
If you are traveling in J then you will have access to Al Mourjan lounge. The lounge has a number of private sleeping rooms which are on a first come first served basis.
If you are not in J then any lounge your OW status gives you access to has no sleeping rooms.