You don't need a microphone to play MP3 files. Steve
You'd need an amplifier to drive a speaker - that module has only enough output power for headphones/earpieces. Perhaps hook it up to an LM386 module?
DFPlayer has a speaker output - you can find it on ali express.I have used this mp3 player in several projects and it worked pretty well. It has two outputs: one for headphones and one for speaker. The speaker output is OK for playing in quiet environment (but it does not have "disco power").You can find a tutorial for this player here: https://www.dfrobot.com/wiki/index.php/DFPlayer_Mini_SKU:DFR0299