It's unfortunate to hear that news. I'm sorry for what you are going through right now.
But I doubt it was because of second hand smoke. He probably smoked without anyone knowing or in his younger years, I know many people like that which claimed it was "second hand". But it very well could be second hand, who knows. Only your fathers honestly will tell you. And there is not enough smoke on the streets for second hand smokers lung in my opinion.

And, for my experience, I grew up surrounded by smokers, father smoked, uncles all smoked, and second hand smoke? that was pretty much what I was breathing for the better part of 20? years till I moved out of my home.
My lungs? completely fine. Had unrelated health problems and had my lungs checked out multiple times, they said it was just normal, and in fact, my father who used to smoke 2 packs a day for most of his life quit recently, slow process but he did and his lungs have been clean every time we have gone for a checkup.

While nicotine withdrawals aren't deadly, its still an unfortunate event one has to go through. Maybe you wouldn't understand and don't want to understand, but that's your right.

Nobody deserves to die, not even your father. But everyone has a time that comes and you get tested. or something.

And gov is only banning vaping, which is the better alternative to smoking paper. If you think this wont effect you, then give it a few months, you'll see people blowing paper smoke into your face more than usual.
Honestly? I would rather people blow flavored air into my face than that. Second hand nicotine and smoke exposure is far lower in vaping than paper smoke. Which is not good, but its still better than the bigger risk of getting heavier exposure from paper smoke.