>>14682828well that was a fucken pain in the ass.
anyway. after you've installed streamlink and VLC (I assume) and set the VLC location in the options properly then create a file name it something like streamlink.bat (it's a batch file).
then copy this into it:
@ECHO OFF
SET /P _inputname= Youtube URL:
@ECHO Youtube "%_inputname%"
start streamlink "%_inputname%" best
save it. then create a shortcut to the batch file, as you need to set the shortcut to launch as administrator for this to work for some reason (idk maybe a windows update?)
then you just start the shortcut, it opens the batch file, copy the URL from youtube then just paste it into the command prompt (it should just be a right click as long as you aren't selecting anything).
press enter and it should launch it.