Thanks for your question and for posting it here in the Community!
If you're using the most up-to-date version of Spotify, you won't see the 'minus' button anymore, but you can still prevent the app from showing you the songs of specific artists by clicking the three-dots symbol on the top right corner when checking an artist's page and then clicking 'Don't play this artist'.
When it comes to the Like button, you'll find it both:
on the left side of the song title onto the playback toolbar, as it's visible in your screenshot;
and also by clicking the three-dots symbol on the right hand-side of each song title as they appear in the playlist.
Hope you'll find this info useful. Let us know if there's anything else we can help with 🙂
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