A bicycle is easier to get started on. To learn balance and steering. I would think if you didn't already know how a 2-wheeled vehicle works you'd have a lot of grief trying to learn it on a motorcycle.
But I heard an instructor in the Motorcycle Safety Foundation class in an interview and he said that a lot of people show up for their beginning class without ever having ridden a bicycle. So apparently you can. I wouldn't though.
Depends ht you mean by "Easy". Without much money it's a no-brainer because you can't buy a motorbike and pay for insurance, fuel and maintenance.
Bicycle is easy to learn and mend, cheap to buy and maintain.
You can't go a long distances easily unless you are very fit, and even shorter distances take much longer than on a motorbike. But you are much more likely to be killed/injured on a motorbike. If I had to choose I'd have a bicycle.