What is the best approach to install windows 10 to new SSD

First, let me say that last night, out of the blue,my PC crashed. Long story short, my Kingston 240gb SSD abruptly died. I'm not sure how long I had it, but it was no more than three years old. The system itself was built in 2011, but I changed the original Intel 120GB SSD to the Kingston. It gave me no prior indications before last night that it was going to die. Basically it went quickly. I thought that I could grab some files from it but it apparently doesn't seem that I will be able to. I ended up going to Best Buy and picked up a PNY 480 GB SSD and a copy of Windows 10 pro. I didn't even have a copy of any OS other than XP.

Here is my plan. I will install the new SSD and load the win 10 OS onto it. Then I want to recover a backup that I performed over a year ago. This backup was on one of my NAS drives. Apparently I procrastinated too long and failed to make scheduled backups of my C:\ drive. I think this will work because the OS I had on my "dead" drive was also Win 10 pro. The backup may be old, but it may prevent me from downloading and reinstalling a lot of apps/programs that I had before. Does this approach seem to be possible? Any suggestions would be greatly appreciated.

As @Ztruker said, you did not need to buy Windows 10 Pro, you could have downloaded it for free from Microsoft and installed and activated it based upon the previous activation of Windows 10 on that computer. You might want to save the Product Key that you purchased for future use and just click the link for "I don't have a product key" when asked to enter it.

But that being water under the bridge now, to answer your question as to how best to install it.... with the new SSD as the only physical drive connected to the computer (other than the Windows 10 USB flash drive or DVD) - boot the computer from the Windows 10 installation USB flash drive or DVD. When given the choice, select the Custom Install option. The SSD should be listed as Drive 0 with nothing but unallocated space. If there are any partitions listed, then highlight each one and click the delete button to delete them until there is nothing but unallocated space shown on the SSD.

Hightlight the unallocated space and click next.

First, I didn't know that I could download it again. I did try restoring the backup without windows 10 installed. It took a while, but when I tried to boot up, I did not have boot manager. I guess it was not in the backup file. Or, maybe I can only backup when windows is present. I don't know. The real problem is that after I purchased the boxed version of Win 10 pro, I looked inside. Lo and Behold...there was no disc!!! This tells you how long it's been since I installed an OS. I didn't know that they put it on USB flash drives. And...my BIOS does not recognize booting from USB! So, I downloaded plpbt to make a disc that would allow the computer to read the USB. It didn't work. Not sure if it was the correct file or not. I'm going to keep trying. I tried getting support from Microsoft, but jumping through all those hoops (couldn't sign in to Microsoft account because I had forgotten my email and password) was confusing. I will try again.

Unfortunately, my pc was built in 2011. The mobo is an Asus and the BIOS is probably outdated. Anyway, I am downloading an ISO file from Microsoft for windows 10. Not sure which version it will be, but as long as it's free that's ok. I will then burn it to DVD and finally finish this thing. Thanks for the recommendation.

Thanks again.

Well, I downloaded the windows 10 OS from Microsoft. It was an ISO file which I then burned using a third party app. I then put it into the DVD reader of my pc and waited for it to start loading. Instead I got "bootmgr missing". I don't know what is going on. Evidently the ISO that I downloaded did not have bootmgr on it. This is truly frustrating.

The iso file I downloaded from Microsoft was about 3.5GB and was only one large file. I took the USB flash drive with windows 10 pro on it and copied all of the files to my laptop. This folder was about 7GB and had numerous files, including bootmgr, bootmgr.efi, setup.exe, and autorun.inf. I took those mentioned files and put them in a folder with the windows 10 iso file (3.54gb) and burned them to another DVD. I was hoping that this would solve the problem, but it still came up with bootmgr missing. I found an old copy of windows XP and put that into the PC dvd-rom just to see if maybe the PC/BIOS was corrupt. It started up and began trying to install XP until I ejected this disc. Maybe I'm doing something wrong, but I don't know what. Any suggestions would help me out greatly.