XPS Desktop, Audio Port Question / Problem

I am about to purchase an XPS Tower for our church. The audio ports on this PC are 5.1 3 jacks on the rear, all output. I am aware that there is a headphone jack on the front in a TRRS configuration. I need to be able to have a line in jack from a sound mixing console to record sermons. The ports are advertised by Dell as being retaskable. I can't get an answer on how this is accomplished or is it even possible? Can I "retask" one of the output ports on the rear to act as a line in? The sound card is onboard Realtek Codec.

Separately, I was browsing around in here and read an article where a USB audio adapter was recommended to someone. It had separate female ports, one for a microphone and one for a headset. 

I must also make clear that I need to have both the line in and line out working simultaneously, since I'm generating sound, (from videos), while I'm recording, (comments from the pulpit).

Any help would be greatly appreciated.

Thanks