18 in Jersey and without a license, do I need to take my permit test?

You sure do: any new time driver has to take that test PERIOD!

Yes, just because you are 18 you are not gifted with all the worlds knowledge. You still are as dumb as when you were 17.

. Start by READING  the Driver's Training manual and you will see how much you don't know yet.   You got to pass tests. to GET A PERMIT(aka Learner's License)

In almost every state (if you're at least 18 years old), you have to take and pass the vision test and the written test before the DMV gives you "permission" to take the road test and obtain a driver's license. 

Passing those two tests will become your "permit" to take the road test; but, if you're at least 18, no special written "permit" is issued to you. "Permits" are issued to drivers under 18, or for those people who don't already know how to drive a car and need to practice driving. 

After you pass the Written test and receive the DMV's "permission" to take the road test, you make an appointment to do so. 

Just because you were nice enough to ask, no you do not. Public transportation is available

Not if you don't want to get a drivers license.

Yes.  everyone must take the test

My understanding is there are 2 parts, the written and the driving test. Most pass their permit and then take the driving test months or a year or so later.

If you never got a permit, I suspect you may be able to do them both either the same day or a few days apart. (Depending on how fast they grade the written)

You may be able to pass the written and then take the driving test minutes later.

They may not let you take the driving test without having passed the written first.

Everyone needs to take and pass the permit test. It doesn't matter how old you are.