How to set default application volume?

gcars06 wasn’t asking how to change how to change application volumes, but the Default Volume for applications before they start. I’m having the same issue plus a similar issue. My computer’s default audio options are set to blast sound without headphones, and every time I use the mic it’s set to the internal one, even when I’m wearing headphones. I would also like to know how to change the default setting for any and all audio volumes on my computer.