5GB on DS920+ how to stream easily 4K movies

Hi, could you please make a video for us Mac users, how to enable USB 5GB adapter so it works with DS920+ (Synology 2.5GbE / 5GbE USB Adapter Setup Guide - DSM 7 Version - YouTube). Would also be great if you can maybe make a video about what is required to stream easily 4K movies that are 100 GB to your TV or streaming devices do I need a 10 gig switch for this or is it enough with one gig the thing that I also think should be mansion is that maybe you need more bandwidth because people are using Wi-Fi or using other streaming devices at home. Do you have any videos how to replace a hard drive?