There is a site online which I cannot recall now, that had a feature where it would give you something to readback, and you could see how much you could get then play it again. Like a robotic voice. Was US based, but still good value
Seconds for live atc ( as sad as it is, there were times training where I listened to this more than real radio). Whenever atc give a call, read it back. Good practice. Now available as an app!
Airband scanner also a good idea if you can afford as you can sit in the cafe and listen.