Permit, as in learners permit, gives you a permit to drive with a passenger beside you that has a full license and has had on for at least 4 years. Drivers test it to be able to drive alone. That's how it is in Canada anyway.
No you do not need drivers ed to take your permit , the permit is questions based off of rules of the road, drivers ed is to teach you how to drive. You have to study the book take test, get your permitthen take drivers ed to get your license.
There is no difference in a learners permit and a permit. People just say permit because it is shorter than saying learners permit. A permit or learners permit lets you drive with an adult of 21 or over with a valid license. A drivers license lets you drive by yourself without the adult.