const artistsAndSongs = { "Keyakizaka46": ["Silent Majority"], "Blackpink": ["How You Like That", "Ice Cream"], "JKT48": ["Rapsodi", "Heavy Rotation"], "Twice": ["What is Love?"], } artistsAndSongs["Babymetal"] = ["Gimme chocolate"]; delete artistsAndSongs["Keyakizaka46"]; artistsAndSongs["Blackpink"].push("Rose - Gone"); console.log(artistsAndSongs);