CB 50 J does not start

In the evening I bought a used Honda CB50J BJ 78. At the sale and the test drive it ran like a one. At home then it suddenly did not jump any more and even after pushing it did not run anymore. Gasoline is in it and the battery seems to be in order. Since I bought the thing only because I bought n car is too expensive I have no idea about it – but I am willing to learn and have already read other posts diligently. I am also looking for some spare parts: Brake lift l for the front brake rubber upholstery for the kickstarter lever end pot/outpuff (is ne “sidepipe” ant) About a manual/reperature book or wiring plan I would also be very happy Thanks in advance – I like to take pictures if you tell me about what.