Well, I think the meaning is pretty straight-forward. He seems to be talking about a parent who used to have a bunch of dreams and ambitions but had to give those up most likely due to the conception of himself. Said parent has had a hard time letting go of those dreams and ambitions and wishes he/she could just go back and change his/her life so he/she could reach those dreams. But because he/she obviously can't do that, they are blaming and taking it out on their child. The child is basically saying that the parent must live with the life they forged in their youth and should not be taking it out on them as their youth is currently the present and they have yet to forge their future and he isn't going to waste it like his parent did.
Well, I think the meaning is pretty straight-forward. He seems to be talking about a parent who used to have a bunch of dreams and ambitions but had to give those up most likely due to the conception of himself. Said parent has had a hard time letting go of those dreams and ambitions and wishes he/she could just go back and change his/her life so he/she could reach those dreams. But because he/she obviously can't do that, they are blaming and taking it out on their child. The child is basically saying that the parent must live with the life they forged in their youth and should not be taking it out on them as their youth is currently the present and they have yet to forge their future and he isn't going to waste it like his parent did.