No you cannot get a motorcycle license online.
To get a motorcycle license you will have to study up on the motorcycle laws and rules just like you would study before getting a drivers license for a vehicle.
So you will have to go to your local DMV and get a study manual for the motorcycle and then go in and take a written test for the motorcycle license.
Then you'll also need to take a riding test where the drivers license examiner will grade you and watch you drive or ride the motorcycle.
Then if you pass the motorcycle driving or riding test you can then get your motorcycle license.
You'll need to go into the DMV and license examiners office to get the motorcycle license.