1-ACC network is part of YTTV package.
2- Games picked up by YES, you would have to watch on Watch ESPN. But it would be available in your area because you don’t have YES. New York people get blacked out when the game is on YES because YTTV doesn’t have YES network. If they did play a North Carolina team, it is possible the game would be on an equivalent to YES in NC and then you would also be blacked out and need to watch it on that channel. Not sure if any local NC channels broadcast games.
3- Yes you can share. There are 2 different ways. You can split the 3 streams. Any time a fourth stream would start the first stream would cut out. You are only allowed 3 concurrent streams.
3b- you can pay an extra 10 dollars for 4k and 20 streams. Some channels still limit to only 3 streams but it’s only like 3 channels I believe. Your “home” address would be able to stream as many streams as you want. Your secondary address would only be able to use 2 streams. If that family member opened up a 3rd stream, you all would be kicked out of everything down to 3 total streams.
I’m not the best explainer, hope this helps. Ask if you got anything else.