I don’t know how to speak to people and I need help

So basically all my life I’ve always been seen as the quiet one no matter the occasion. I am one of eleven and when I look into the life’s of my siblings it feels like they all have unique personalities or something that makes them stand out and when I look at myself it makes me feel as if I don’t have a personality at all. When I’m around them or any group of people, I feel like the odd ball out. Like I can never contribute to the conversation or relate to what is being said. And it’s not like I don’t want to speak to them because I actually really want to, I just genuinely have nothing to say. It feels as if in conversation my mind is completely blank or even fogged if that makes sense. Not a single thought or idea goes through my mind to add to any conversation. It always makes me result to generic responses. I’ve even been told that I “speak in phrases.” And this isn’t a problem that I have all the time just more times than most. Like for example I randomly get boosts of energy and it makes me want to talk nonstop and I truly like this feeling because it makes me feel like “me” if that makes sense. But these moment are always short lived because after a while I resort back to the quiet, nonchalant, boring version of my self. It’s like I experience very high highs and low lows. I just finished my first year of college and I’ve become more self aware of this version of my self and how it makes me be perceived by others. I notice know that I struggle to hold conversation for more than a couple sentences and I can notice the people around me have little interest in what I can manage to speak about and that they are becoming bored around me and I hate it. I never want to be the “boring one” or the “lame one” so now I try my hardest to come out of my shell and try new things to help improve my social skills. I know this process is a journey but if anyone else has any tips they would be greatly appreciated.