Win 7 preinstalled with download rights: still Free upgrade to Win 10?

With a fast processor less than an hour.

If you follow all the steps in tutorial it can take a few hours, but you can also spread it over several days, like doing the Setup after install later to take a break and while you get all Windows Updates downloaded in the background.  But there shouldn't be many if you use the latest media, especially if you wait a few days for Version 1909 to be loaded into Media Creation tool.

Yes, I did read it, it's just that I had to deviate from it by going into the BIOS first, so I wasn't sure what to do after exiting the BIOS...but now I see that I still have to press F12 (on my pc) after leaving the BIOS, Thanks.

BTW, how long does this process take?

Yes, that is correct.  I clearly state how to boot the media and illustrate it in the tutorial.  You should be following the tutorial if you want to do a Clean Install with further support from me.

Make sure during the booted install to follow the illustrated steps to delete all partitions down to Unallocated Space to get it cleanest, then click Next to let it auto-create the needed partitions, format them and begin install - this makes it foolproof.

So I press F1 to go to setup and properly configure the BIOS with UEFI, then I exit BIOS and save changes, THEN do I immediately press F12 to go to the boot menu to make sure it boots from my install disk and not into Win 7?  Or you're saying that it will automatically boot from my usb or dvd boot disk?  Or must I change the boot order in the BIOS as well, to boot from (what)?  Kindly explain...

Please see picture. 

Thanks again for your help Greg.

The steps to post a Win7 Disk Mgmt screenshot are the same.  I copied that tutorial from my older Win7 tutorial for the same thing.

The Manual refers to UEFI, so right before reinstall you'd go into UEFI Setup via the key given on first screen to access UEFI Setup, change settings to UEFI enabled, CSM or Legacy BIOS disabled, Windows Boot Manager is set first to boot (or will invoke itself during install). 

Then during the booted Custom install follow the steps closely in Clean Install Windows 10 to delete all partitions down to Unallocated Space and click Next to let it auto-create and -format needed partitions and begin.  This makes it foolproof. 

Your settings may vary a bit so read your Manual to fully understand the UEFI settings if there is any question.