Upgrading from Win 7 to Win 10

As is no doubt widely known, MS support for Win 7 ends mid-January. Can anyone offer any sound advice, ideally based on personal experience, as to how to go about upgrading from my current Win 7 64-bit desktop platform to Win 10? I'm sure I could do this myself but I'm reluctant just to stick a pin in one of the many Internet pages which promote a DIY approach and then hope for the best.
Incidentally, I have Win 10 installed on a laptop and that was a paid-for upgrade. Will I be able to use the product key for that install to authorise the install for the desktop - or do I need to buy a new licence?
If whoever replies to this needs any further info as regards current desktop hardware, happy to provide? Thank you.
Bob
Incidentally, I have Win 10 installed on a laptop and that was a paid-for upgrade. Will I be able to use the product key for that install to authorise the install for the desktop - or do I need to buy a new licence?
If whoever replies to this needs any further info as regards current desktop hardware, happy to provide? Thank you.
Bob

It's likely you'll need to buy a new licence, unless you're going to stop using the Laptop - in this case you could transfer the licence:
https://www.windowscentral.com/how-transfer-windows-10-license-new-computer-or-hard-drive
https://www.windowscentral.com/how-transfer-windows-10-license-new-computer-or-hard-drive

It's been pointed out on a few forums, I think, including this one, that it might still be possible to upgrade for free.
It's worth a try before you part with any cash.
As for your existing "7" licence, that should be stored somewhere (BIOS?) and even if you go the nuke and fresh instal route, (my preferred option) it will still be recognised and I doubt that you'll need it.
As always though, make sure you've backed up/made copies of everything that you need or consider important.
What you're about to take on is actually dead easy.
Good luck!
It's worth a try before you part with any cash.
As for your existing "7" licence, that should be stored somewhere (BIOS?) and even if you go the nuke and fresh instal route, (my preferred option) it will still be recognised and I doubt that you'll need it.
As always though, make sure you've backed up/made copies of everything that you need or consider important.
What you're about to take on is actually dead easy.
Good luck!

This "Is Windows 10 still free?" popped up in a newsletter this morning.
Might be worth a look.
I also stumbled upon this one in a folder full of old bookmarks.
It's a bit long in the tooth now but who knows? Again, probably worth a look,
Might be worth a look.
I also stumbled upon this one in a folder full of old bookmarks.
It's a bit long in the tooth now but who knows? Again, probably worth a look,

You should be able to use your W7 license on a clean install of W10, see here. Note the ProduKey tool mentioned in the article.
And no you can't use your laptop license anywhere else - one use only.
When searching Google for things like this I find it helpful to restrict results to the past year - that way you know you're getting reasonably up to date info. Also read any articles to the end - including any comments. You may get some useful info along the way.
If you have one disk with your OS, programs and data on it then backup your data - twice! Two copies.
Ideally you'll have a spinny disk with your data on it and a SSD with your OS and programs on it. Then I would recommend getting a new SSD to clean install W10 on. I have 2 SSDs that I swap between every year with a clean install. I just disconnect my spinny disk when I'm installing so I know it's safe, take out the working original and put in the spare to clean install on.
Having two disks takes the pressure off to get it right first time, as you can just plug the original back in and you're working again.
Hope this helps. And makes sense!
And no you can't use your laptop license anywhere else - one use only.
When searching Google for things like this I find it helpful to restrict results to the past year - that way you know you're getting reasonably up to date info. Also read any articles to the end - including any comments. You may get some useful info along the way.
If you have one disk with your OS, programs and data on it then backup your data - twice! Two copies.
Ideally you'll have a spinny disk with your data on it and a SSD with your OS and programs on it. Then I would recommend getting a new SSD to clean install W10 on. I have 2 SSDs that I swap between every year with a clean install. I just disconnect my spinny disk when I'm installing so I know it's safe, take out the working original and put in the spare to clean install on.
Having two disks takes the pressure off to get it right first time, as you can just plug the original back in and you're working again.
Hope this helps. And makes sense!