<human>: Can you succinctly summarize the text in 1-3 sentences?

Ok, so background: my parents got divorced about two years ago, my dad now lives with his father, taking care of him, but also because he can't afford his own place as he only has a part-time job. 

I am in my first year of college in my hometown and my dad picks me up from my campus two days every week after he picks up my sister from the local high school. We generally ride home in silence, sometimes there's small talk. He also sometimes asks to come in and hang out after and if we say yes we'll just sit around and watch tv.
My dad asks my sister and I to go to dinner, lunch, movies, whatever, all the time. He also just bought my sister a video game that she didn't want (he was joking around with her about buying it so they could play together, she said no, then he actually bought it). 

It's not that I don't love my dad, it's just that we have absolutely nothing in common and I never know what to talk about with him. He is currently in a committed relationship so I know he's not completely alone which makes me feel better, but I know he wants more of a relationship with his daughters that I don't know how to give him. I feel like I'm using him on the rare occasions that we do hang out (he buys us lunch, takes us to movies, we recently went to a football that cost $10/person and he payed for both of us).
<bot>: My dad wants more of a relationship with my sister and I but I don't know how to do that because we have nothing in common.