Hi there! First, sorry for the delay in response. It can get busy around here! My heart goes out to you over the loss of your dad, and I give you credit for wanting to make the most of the life you have. It take effort but I feel confident you will benefit. 😀
As for the breathing exercises you shared, the photo is a bit small so it's hard to tell what I'm looking at. Feel free to share a link to a website you saw. In general, I can say that breathing exercises are useful for virtually every person with COPD, even if they are very severe.
It looks like you posted some kind of device, so I want to share that some people do find that different devices help. One example is a flutter valve. You blow into it and it creates vibrations that help you bring up mucus easier. There is a brand called Acapella that is inexpensive, or you can ask your doctor if they have something similar to give you.
A good thing you can do regularly without equipment is pursed lip breathing. Super easy and can be a big benefit. Here's a video about it:
https://www.lung.org/lung-health-diseases/wellness/breathing-exercises
Keep asking questions. We're here for you! -Melissa, copd.net team