What amenities/services do European train stations have?

Most European train stations have secure luggage storages, where you can leave your things. Keep in mind that luggage storage isn't a free service and charge rates vary depending on the specific train station as well as the amount of time you plan to leave your things for.

Not all European train stations are equipped with WiFi, yet it might be available on some stations for a fee.

All European train stations have public restrooms but note that pay toilets are a common thing in Europe and train stations might not be an exception.