Music that I've downloaded onto my device separately from Spotify

[benjatheworst]

I am using Spotify on my laptop (Windows 10) as a Premium member and I am trying to add music that I have downloaded onto my device into my playlists as I have done in the past, but I cannot seem to find the tab I used to use to access the music I had downloaded onto my laptop. I remember there was a tab on the left-hand side above where my playlists are listed that would allow me to see the music that I am currently trying to access, but it is not there anymore. Is there any way currently to play music outside of Spotify on Spotify?