I don't know what to do

I've been struggling with what to do, I feel like I've never really been apreciated since I barely talk to anyone at home, I'm always silent when we're at the dinner table and it's because I always get cut off when I try to talk, now I'm not mad or sad about that I'm just feeling like I'm missing care my parents are always busy and I never really get the attention I want, we only speak when there's something we need, I just want to be a good example for my sister I actually want to do something that proves that I'm responsible, I'm to scared to ask because all I think is "Maybe they'll laugh at me" Or they won't take me seriously, my physic is not that great so I think I'm my eyes my parents don't see me as responsible but how can I prove them wrong in a nice gentle way?