I think my dad is such a callous man
What makes you think he's so callous?
He works a lot and frequently forgets about me.  Sometimes he drinks too much, as well
He shouldn't be treating you that way.  Does he ever get violent when he's drunk?
No, nothing like that, he's just distant.  But, I have worked out that if I mow his lawn, his mood will improve.
Your father shouldn't be so callous and uncaring toward you, and i hope that you don't blame yourself for the way he acts.  It's good that you are willing to help him out, and maybe the two of you can find a household project to work on together.