When I bought a new Suzuki B120 from Chatham Motorcycles in Edinburgh, the salesman asked about my riding experience - none. (Many years as a pillion, but none at the front.) Took me and the new bike outside, next to the kerb on a public street. He sat on the bike and demonstrated putting the bike into gear, moving away and stopping. Then he asked me to try. Stalled it the first time, so he explained a bit more about coordinating clutch and throttle. Pulled away successfully second time, so walking alongside he told me to change into second. Which I did. Then stop, which I did. Told me I could practice as long as I wanted to and went back into the shop. The sum total of my rider training.
The law changed a few years later, bringing in compulsory training before you could venture on a public road - a car park element with cones etc then accompanied on-road riding, theory test etc. All after my time.
Did my driving test a few months later - that was not very hard. Tester, on foot, observed you driving around a few streets, road positioning, priority at junctions, signalling, proper control of the machine, slow riding, emergency stop. And two or three theory and Highway Code questions.