If you don't want Apple Music to make recommendations, then turn it off at Settings > Apps > Music > Use Listening History.
Most users will use Siri to tell Apple Music what songs they like and don't like, so the recommendations are tailored based on your listening history. It is not required and you don't have to do it. You can do the same in the Music app for Genres, Artists, Albums, and specific songs.
You should also check if you have AutoPlay turned on. This will play similar songs after a playlist has finished or any queued songs played. Go to the Music app or the mini player on your Lock Screen and choose the button with 3 lines. Then notice the infinity icon on the top of the screen. If it is selected, that means AutoPlay is on, so you just need to tap it to shut it off. You just need to do it once and that setting will remain until you change it.
Queue up your music on iPhone - Apple Support (SG)