- Connect the battery pack to your computer via a USB-C to USB-C cord (other types of cords won't work).
- Connect your phone to either one of the two USB-A ports on the battery pack. Make sure you have the right cord to make the connection.
- Double-press the side button on the battery pack to enter the USB hub mode.
This setup works. I've verified it with a MacBook and an HP laptop.
One Suggestion: You may want to try this a couple of times in an environment where you have alternative methods to access the Web. In doing so, you can be sure if the tethering works with your laptop. If it doesn't, at least you have a backup method to get on the Internet.
One Caveat: When in the USB hub mode, there won't be fast charging.