how to help my dad with depression?

my dad has been depressed for as long as i remember, but i've only started understanding it as i've gotten older. all i want to do is help him, i just want to give him some hope.

i make sure to spend alot of time talking to him every day now, most of the time he's alone in the living room, he has a bad relationship with my mum and my siblings are pretty anti-social.

he always talks about how he's going to die soon . he's only 40 something. he sleeps on the living room floor with my brothers old duvet. when i ask why don't you buy yourself a new duvet, he says that by the time he's gone the duvet will still be new, and it will be a waste. even when his shoes have holes in them, he wont buy new ones, because he'll be "gone soon".

at night he shouts/screams/groans alot, i thought it was during his sleep, but he told my the other day that it's because his heart hurts alot and his chest feels heavy at night. so he has to let it out.

he has alot of financial issues/debt. he made alot of stupid decisions in the past that made him lose alot of money. he gave alot of his money to his mom/family members, who doesnt even give damn about him. he always does so much for others, but no one gives him anything in return. he also talks about how his dad was the only person to care about him, and his dad passed away when he was a kid. obviously i plan to help with this when i start working, i want to give most of my salary to help pay his debt/rent etc. and in the future i want to help buy a house

please tell me what else i could do. therapy won't do anything, my dad works alot and he won't believe in things like therapy. i dont know what to do, i just want him to be happy