Why is my internet connection so slow on Windows 10?

[Windows Central Question]

My HP was totally fine until I upgraded to Windows 10. I literally have to sit directly in front of my WiFi (I'm within 1.5' ft. now) and it is still painfully slow. It can take up to 20-minutes to type a 2-line email. I've been doing what I can on my phone. I'm not a techie person so I'm not sure at all what I need to do to speed it back up. Help someone!!