Auto-play an audio file, then record when they paused it

Hello!
I'm very new to anything involving custom code! First, I want an audio file to auto-play (play immediately when they get to the question's page). I tried the following HTML code I obtained from a prior posting:

When I enter this into the HTML view of the "question," for some reason, it doesn't save it when I go onto editing another question. Am I doing that correctly? Is there something else I need to do?
Also, I would like to have the audio file auto-play, then have participants pause when they've made a decision (this is an audio-recording of an interaction between two people, and I want them to pause/stop/move on from the video when a person in the audio-recording has said something specific, then I need data on when they made this decision). Does anyone know how to do this?
Any help is greatly appreciated!