Improve social skills in university

Hi,
So I’m a university freshman. I have really bad social skills. Like in highschool I was an introvert. When I came to uni some people hung out with me and now are like ignorant jerks. And now its tough for me to find groups because I am not that interesting or did not socialize well at the start. I want to improve my speech and gain interest from people and hopefully talk to girls properly and shy away. I want to get invited to parties and hangouts. I do not know how to do so and so I need help.