How Best to Install Windows on Multiple Unpartitioned Drives

Hi, install the O/S on your SSD. When you clean install Windows in the usual way, it creates all the partitions you need.
(See tutorial 'clean install' if unsure).

Bear in mind that normally you will be installing programs on that same disk.

You can disable hibernation and hence fast startup as these are not really useful given you have a SSD.

Disk imaging
As early as you can, start routinely and regularly using disk imaging as is so very very often recommended here e.g. Macrium Reflect (free). You will need large enough external storage for your sets of image files. (Yes, another disk.. or disks).

You will be tempted after installing the O/S to rush in and configure and install like mad. Be disciplined: keep a simple record of changes, and periodically update your disk image. That was should something go wrong you've not far to go back.

System Restore: is not enabled by default. Whilst not as robust as in Win 7 (it may suddenly fail to complete restoration, then some months later start again) - when it works, it's great - no effect on personal data. There's a tutorial on scheduling the creation of restore points.

Personal data
Plan from the start to keep as much of your personal data off C:

Why? Because it's most likely the disk or partition you will need to restore from your image files will be C: - and all data on that will then be as of the date the image was created.

Whilst it is possible to relocate the default library folders Documents, Videos etc, it is also possible to slip up and make horrible mistakes in this seemingly simple operation.

Further, many of the programs you install create folders in these. My view- best left on C:.

Create your own folders for personal files on your hard disks - or even a separate partition on C: if you wish.

As to your use of the hard disks- that's entirely up to you in terms of what you're planning to put on them.

License
It has been possible for quite a long time to legitimately get a license for Win 10 Pro for around £40. There are 2 threads on this magazine-based offer.

Disk Monitoring
Whilst the very act of creating a disk image verifies the integrity of the use part of the partitions imaged, that leaves other areas unchecked. Consider installing Crystal Diskinfo (free) and leaving it to run and monitor your disks and report any degradation against thresholds to give you an early warning.

Windows Updates:

Configure Active hours, and settings related to restarts, and set updates to Notify in Group Policy (Pro) so you have reasonable control and are not interrupted by Windows Update.