The AI answer pretty well nailed it.

No. That depends on each person and what they do after they have been diagnosed.
Keep doing what you were doing, it will continue to progress as it has been. Be careless, smoke, breathe in bad air, not listen to your doctor, or keep catching colds you will progress faster. Learn about the decease and the things that affect it and change everything you can live decades. All up to 'You' and what effect you put into it.

I think that totally depends on how you're conducting your day-to-day activities. I ignored my SOB for a few years until I was forced to confront it head on with COVID. Been on supplemental oxygen for almost 5 years now. Was diagnosed at Stage 3. I've been put on a high flow concentrator for my house as of this past April. Do better than I did. Get some exercise every day, practice very deep breathing, and pursed lip breathing. Steer clear of people smoking, and when you feel fatigued, do NOT feel guilty about kicking back and taking a snooze. Also...get yourself a pulse oximeter (those don't require a prescription) and start monitoring your BOC. If you're consistently reading less than 88%, you need to see a doctor and get a referral to a pulmonologist who can zero in on the myriad of symptoms and figure the best course of action for you.l

6 years ago I was diagnosed with mild emphysema with no symptoms. Kept puffing Thats why they call me stupid. SOB started about a month ago while doing yard work digging mostly wholes for 5 gallon plants. I can walk 3 miles not feel to much but using my upper body starts the SOB bad. Testing Wednesday to see what stage I’m at. Give yourself a chance….STOP SMOKING OR THEY WILL-CALL YOU STUPID.