Depends on where you are, many states now have a law forbidding drivers under the age of 18 from having passengers, this is an effort to cut down on teenage traffic deaths. if you are not sure, call your local dept of licensing.
yes they can
You have to drive with a licensed Driver.
Only if you also have a licensed driver with you [ and of course , kid in a safety seat ].
You can drive with any licensed driver
Any licensed driver can teach another person IF they have a Learner's Permit. Ages of the licensed driver don't matter but the licensed driver should be experienced.
yes, you can if you are a fully licensed driver.
Yes, as long as the other person is a legally licensed driver.
During the first 12 months after you are licensed, you cannot drive between 11 p.m. and 5 a.m. and you cannot transport passengers under 20 years of age, unless you are accompanied by a licensed parent or guardian, a licensed driver 25 years of age or older, or a licensed or certified driving instructor. All the details are in the driver's handbook (related link).
Both are held liable.
Yes
No. You need a licensed driver with you while you drive.
Yes, YES as long as you have your licensed driver with you.