Great questions!! It depends...
Yes, you can connect to a newer laptop / tablet (I source from iPad Pro).
No, you cannot play it using whatever application you are in aka windows media player/youtube etc.
But you can source from Pandora, Sirius XM, iHeart Radio,etc.
No, you do not need a digital library on a drive somewhere, as this is designed to convey music from a streaming source.
I also source from an App known as Airfoil. It allows you to stream media from the internet through iTunes.
Sorry the answer is so ambiguous. You may wish to Google Airfoil App, to see whether it might help you. The short summary is: you cannot do exactly what you were hoping to do, but you can stream a wide variety of sources through your tablet & the sound quality is awesome! I attached 2 photos of my W9's, set to stream Sirius XM through Airfoil.