It's an iphone 6s, yes it's connected to the internet, and yes it's compatable with iOS 13. the error is "software update failed" "an error occured downloading ios13."
It received the new 13.3 update and updated no issues. In some instances it's faster than my 8, others my 8 is faster. Very impressive for an older phone. Start up was faster on the 6s, as was loading news+, most apps were basically the same or the 8 just a fraction of a second faster. Amazon prime was very much faster on the 6s as well. Crazy awesome. I always said that was the best phone apple ever produced.