How to add music to my Samsung Android phone?

(I just got my dad's old phone today.) I tried adding my music files to the SD card. I made a new folder, called it "music", and pasted my music files into it. I can access them by going to my files from the menu, but then it only allows me to play the songs one by one instead of making a playlist or something and allowing me to play them all automatically, which is what I want. I checked if there was already a music folder before I made one, there wasn't. And it seems I need to download some kind of software to directly connect the phone to the computer, which it hasn't been able to. I went to the music player on the phone, but there's only this one song (which I think may have been recorded? I don't know), and there seems to be no way to add my music to the player.

(Model GT-S5570I, Android version 2.3.6, if that helps.)

(New things can be so complicated, dude.)

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