How to stop staring into space and “make good conversation?”

I met my girlfriend‘s family for the first time today for the holidays. I tried my best to ask everyone good questions and participate in the conversation at lunch. They treated me to their traditional foods and it was really good and I brought everyone thoughtful presents. So, basically after lunch was over I made some conversation by asking my girlfriend about the new art on her wall, but then after a while, I kinda just started staring at the window and staring into space and she asked me so what do you think of everyone sort of like lull in the silence and then I answered and such, and then she asked about my meet up at work the other day that she couldn’t go to and I answered. I then started explaining to her how a certain board game worked that she just got because I played it before and we were going through that. Anyway, my girlfriend has said before that she doesn’t think I’m very good at conversations in person so I feel like she’s alluding to the fact that we have those dead silences and we took the ASQ together and she scored like a 13 or something and I’m at 36 but anyway that was really helpful. She said it was helpful for her, but she has told me before that she feels like she has to carry most of the conversation anyway I don’t know if I’m just being insecure overthinking this but she did invite me to spend New Year’s Eve with her family in a couple of days.