Can someone define and explain the patriarchy for me?

I get that the general idea is that it's a "society built by men for men"

But it feels incredibly abstract and yet I routinely get people using it to basically blame me for all that is wrong in the world as a "cis het male" (too bad I'm not white)

As someone that has suffered abuse several times in my life, and who has never really felt the privileges of being a "male" (since when did we stop just saying guy?), I'm having a hard time seeing the patriarchy as actually real and hurting everyone.