Please have a discussion with your Doc about joining a Respiratory Rehab program. These are structured "exercise" sessions where you are monitored and Oxygen readings are taken while you build up your stamina over a 6-12 week course.
There are similar online courses and DIY activities you can do at home. But you have little way if measuring whether the progress can be maintained. Hearing about your progress from professional Therapists goes a long Way.
Let's face IT. If you are not comfortable with your breathing ability around the house, you will deny most opportunities to venture outdoors for social activities - when in fact you might be able ENJOY them more!
The World 🌏awaits YOU.!
be Well.
To join pulmonary rehab you must have already quit smoking though