You can ride an electric bike almost everywhere in the EU if you’re 14 or over, as long as it meets certain requirements.
These electric bikes are known as ‘electrically assisted pedal cycles’ (EAPCs). You do not need a licence to ride one and it does not need to be registered, taxed or insured.
An EAPC must have pedals that can be used to propel it. (If not it would essentially be an electric motorbike).
If your electric bike doesn’t meet these regulations – either because the motor is more powerful than 250W, or if it assists you when you’re riding more than 25KM/h / 15.5 mph – it will need to be registered, insured and taxed as a motor vehicle. In this case, you will also need a driving licence, and you must wear a motorcycle helmet. On a side note, plenty of electric bikes have a button on the handlebars which disables the speed limiter.