This guide assumes you already have a clean raspbian with all necessary network stuff configured and ready to go. Here is where we start. Basic install routine for all Linux distros (i guess).
mpd
The Daemon
https://www.musicpd.org
ffmpeg
for video and audio conversion
https://www.ffmpeg.org/
youtube-dl
for downloading youtube videos and other streams
https://github.com/rg3/youtube-dl
mpc
to control the Daemon
https://www.musicpd.org/clients/mpc/
ncmpcpp
Commandline player... next lvl control of the Daemon
https://rybczak.net/ncmpcpp/
M.A.L.P.
MPD Client for Android
https://play.google.com/store/apps/details?id=org.gateshipone.malp
MPDroid
MPD Client for Android
https://play.google.com/store/apps/details?id=com.namelessdev.mpdroid
Rompr
Webinterface... ultimate control of the Daemon
https://fatg3erman.github.io/RompR/
tilda
nice terminal that works well together with ncmpcpp (for client only, no use on raspi)
https://github.com/lanoxx/tilda
GPIO to control the Daemon directly
to be able to press some buttons wired to the pi
https://pypi.org/project/RPi.GPIO/