if you are actually the age your profile says you are id suggest to move out as soon as you can. if not theres not much you can do besides nag them to try and quit. as a smoker myself id suggest suggesting to them to try vaping. its muuuuch cheaper and your dads lungs will benefit from no tar and smoke. (no more coughing)

If you are in USA, you know cigarettes are about $10 per pack.

One way to smoke cheaper is to get a machine like in the pic, buy bags of tobacco and the tubes, make one's own cigarettes. It is not as convenient but way cheaper, comes out to maybe $1.50 a pack.

One would need -

Cigarette machine (about $60)
box of tubes ($5)
bag of pipe tobacco ($8 for 6 oz) One 6 oz bag renders about 130 to 150 cigarettes.

All this can be found at a lot of tobacco stores.

There's youtube videos showing how to do it, pretty easy but the cigarettes can be hit or miss because of the texture of the pipe tobacco. Try not to overpack the chamber. Takes a bit of practice.
Even if half the cigarettes do not turn out quite right, it is still cheaper than store-bought.

Machine -

Tobacco (other brands and flavors available) -

Tubes (I had the best luck with this particular brand. )

When you grow up, you can move out and live by your own rules.

But you have no say when you’re living under someone else’s roof.

Well when you can. It's okay to distance yourself from your family for your own sanity.

reminds me..

time for a bunga... cheers 🚬

Buy them on the rez