If you are just going to run Roon on a NUC, then personally, I would install ROCK on it, instead of using Windows 10 on the NUC. That Intel NUC Kit NUC8i3BEH that you referred to earlier comes with a Windows 10 license (which may be non-transferable). So installing ROCK on that kit would mean you are throwing away the cost of the license. It would be better to go for a “barebones” NUC without a Windows license. With this, you need to purchase the RAM and the M.2 SSD separately and assemble the kit yourself, but this is easy to do for most people. Suitable barebones NUCs, memory and SSD are listed on this Roon Knowledge Base page.
If you use one of the NUCs recommended by Roon Labs, then you will get full support. ROCK can also be installed on a wide range of standard PC hardware (we call this a MOCK system in the Roon community - search for “MOCK” in the Tinkering category of the forum). However, be aware that using a MOCK system is not officially supported by Roon Labs.