​@Tleggs  Before your upgrade did your other device support 5G and were you getting 5G services?

Some devices you may have to force 5G also regardless of the network checker which is only a guide it may state 5G service for your post code but infact no 5G service in the real world. 

WiFi outside of you home in other locations you need to use these services some a free other's you'll have to sign up and pay. Once you've set up and logged on to these WiFi hotspot you be able to connect to them when you have your WiFi enabled. Many places like airports, shopping malls, sport centres, train station, hospital will have access to their WiFi network.

Joe