Question/Help Needed: Boomer who is totally inexperienced with DACs and streamers.

It looks like the BlueSound has optical and USB outs...so would I connect one of them to the corresponding input in the amp/DAC?  I guess then I control what I play via a phone or tablet?

Avoid using the optical out and use either its coax or USB, and then yes you’d use your phone or tablet with whatever streamer/app you’re using. 

Looking at this...and will check the other suggestions.  Thanks to all for taking the time to respond to my questions..... 

That Echo streamer doesn’t seem to support Wi-Fi if that’s important to you.

There is an alternative that costs less and features much of the same integration - the WiiM Pro - link. Normally it’s $149, but it looks like it’s on sale for $119. Like the Echo device, you’ll need to connect it to your NAD DAC module using an optical (TOSLINK) cable.

Here’s some more info - link

As  a fellow boomer I struggled mightily understanding streaming and bits and days. Go slow. I turned the corner with a dedicated streamer (innuos zen mini) connected directly to my router. Plus incorporating stand alone sacs progressively moving up the ladder.  And during times of trouble bluetooth can be a savior. 

You really should go spend time with a good dealer.