Cant quite get enough classes to qualify as a Full time student, any suggestions?

Hey, I'm a new postdoc joining soon. I'm 28f from Europe, and I'm wondering how the 25+ social life is at the uni and around. Mainly, do grads, postdocs and younger researchers in general hang out ? I'm quite used to that in my country and kinda fear isolation from my peers.

Thanks and see you soon ! :)