XPS 15, U2723QE, connection help

May I ask for your advice on connecting an XPS 15 notebook to the U2723QE?

1. what is the difference between ports 5 and 8?

2. in order to use the monitor for video output (4K@60Hz) and as a USB hub at the same time, do I need to connect two connections to the notebook or is one USB-C connection enough (via port 5 or 8)?

3. is power delivery available on both ports 5 and 8?

4. can I also connect (directly) from a Thunderbolt 4 port on the notebook to port 5 or 8 on the monitor?

Thanks in advance!