Getting a new pc

[#1]

New pc arriving to replace my current one. I only intend using the one pc or now and will switch the dongle to the new one. What else do I need to do to transfer the Plusnet service to the new pc?
(If this is covered elsewhere my apologies I couldn't find it when I browsed through  a few pages of topics)

[#2]

All you should need to do is set up the dongle to the same as you had before, same ssid & password.

[#3]

I had problems with my pc including connections a couple of years ago, and a pc engineer introduced the dongle at the same time as he fixed the pc. What I'm hoping is that when I transfer the dongle to the new pc something appears on the screen to guide me through, but is anything ever that simple?

[#4]

Depends on your new pc, you may not need to use the dongle. How far from the router are you, and what is the new pc a laptop or a desktop?

[#5]

I'll be 10feet from the router and the new piece of kit is a desktop but it does not have an internal wireless connection. New (refurbished) pc arrived a short while ago and I set it up in the kitchen just to make sure the basics worked ok, and they do. Where it is at the moment is about 20feet from the router and two internal walls between. I have tried putting the dongle on it and, although I get a good internet connection on my mobile in the kitchen, I got a 'nothing doing' on the pc. The dongle is a T-P Link 150mbps. I didn't install it  on my old pc so would there have been software involved?

[#6]

What OS?