If someone is exposed to secondhand smoke often and doesn’t have lung cancer, but starts to show early signs of it, then will it save them if they cut off/reduce their exposure to secondhand smoke before the cancer actually develops? Or is it too late?

My dad was diagnosed with lung cancer last week and he is having his left lung removed this Friday. Today his nose started to bleed. It wasn’t bad but I was wondering if that’s normal and/or something to worry about. Tomorrow he has a doctor’s appointment but I just thought I would ask.
I’m just not familiar with any of this. I just know it’s all respiratory so I wanted to be sure.

Is it a terrible cough, constant, or just a cough here and there? I have never smoked before i’m only 15 and I have been to the doctors twice one said I had allergies one said I had Bronchitis neither took a x-ray and I still have this small-mild dry cough. White phlegm no blood or fever nothing other than a cough. Breathing is fine. Could I have lung cancer? I worry too much (because I’m a hypochondriac)

My mom was diagnosed this past week with Stage 4 adenocarcinoma lung cancer. We do not know if it is small cell or non-small cell. I have been reading like crazy and found most passed from non-small cell within 3-6 months. but is there any change in life expectancy with small cell?? Any and all answers would be greatly appreciated. thanks

My husband has had copd for 4 years and now has lung cancer and also has traveled to the lymph node, what prognosis will he have with no treatment?

My grandfather is currently in the hospital with pneumonia. He has a mass on his lung and they said they are going to be testing for tuberculosis that he may have gotton when he served in the Korean war nearly 60 years ago. They are also going to test for lung cancer. He’s lost 15lbs in a week, he gets the chills and he has a cough..I’m not sure what else hes feeling. Anybody know any knowledgable information on these 3 diseases?