Network new iphone se should be connected to

I was trying to connect my new iphone se to bluetooth in my car. I think I accomplished that but I got an email saying something about ios and a third party network.  When I was trying to find out what network I'm supposed to be connected to my home wifi came up and I signed into that.  Then I got a warning that network is not secure. Am I supposed to be connected to the Xfinity network? I'm all freaked out!