we've seen the problem here before and it's due to a weak wifi device in the Dell computer. Try using a USB wifi instead, which you can get for $15-20.
My computer (XPS 13) came with Windows 10 installed. It's very finicky about wifi. The computer thinks it doesn't have a wifi adapter at times. Drivers are current, and the adapter came brand new in the brand new computer from Dell, so you'd think it would work.
At home, it often takes at least one reboot to get a good connection. And often it will drop the connection after a while anyway. We even got a new router to see if a more modern system would help... not much.
At work, it connects and stays, but doesn't remember the connection so I have to tell it to connect on most days.
When traveling, it often won't connect to wifi no matter what I do. If it looks connected, it only says "limited" and no amount of forgetting the network and rebooting the computer changes that.