answers:

You don’t have to take a class, you can get the permit at the DMV by taking the written, then issued a permit. For the endorsement you have 2 choices. With the permit you can then take the MSF class (there might be other classes that can get you the endorsement, like the Harley Riders Edge class), and there is a riding test you must pass at the end and you have the endorsement.
OR
If you don’t want a class, you can also take the “MIT” (Motorcycle In Traffic) test at the DMV. You wear this radio receiver on your back (in a vest they provide) with a speaker that fits over your ear inside the helmet. The DMV examiner follows you in a car and runs a test very similar to a car road test (next street turn left, pull over, do a U Turn, etc etc). So you pass the roadtest and you get an endoresement, so very much like getting a car license.