Stream purchased iTunes contact on Android?

My mother in law purchased a lot of music off of iTunes over the years when she had an ipod but has an Pixel as her phone. She wants to stream the music from her phone to a bluetooth speaker from her phone. I know very little about Apple and even less about iTunes. I do know what should be easy Apple can make difficult when it comes to moving between platforms. Can this be done? What is the best way to go about it? Thanks