How do I get wifi to connect automatically and stay connected?

Wifi is suppose to connect automatically and stay connected but doesn't. Various error messages and I have tried every fix that I am technically competent to try and understand. For example, "DNS probe finished no internet". "ERR network change". "Problem #007". In lower right corner of screen wifi icon shows wifi not connected but when you click on it wifi is connected. So, I disconnect and re-connect and wifi works sometimes. While the computer indicates there is no wifi my phone is connected to the same network. My laptop is connected to the same wifi network. And I didn't have this problem until I "up graded" to Windows 10. So, what is the fix? Why does the computer connect to wifi and then for no apparent reason disconnect? Why doesn't the computer automatically connect to wifi as programmed? If something was broken yesterday then why isn't it broken today? I'm not very techie which may be apparent from my post. Very frustrating but thanks for the help.

Open a cmd prompt type

ipconfig/all

post results

Windows can not find ipconfig/all. Make sure you typed ........

Looks like a pop up window flashed for a split second then disappears. Nothing else happens.

Ok, here comes my lack of technical know how. How do you "Try it in an Admin Command Prompt, then File, edit and save"?

No such option when I do that.

When I hit Windows X a black pop up window appears with 17 different options, command prompt is not one of them.