Hi Mark, we can do some checks ... [ starting from https://wiki.centos.org/Manuals/ReleaseNotes/CentOS6.8 ]
1. No versions of CentOS 6 will work with Secure Boot turned on. Secure Boot must be disabled to install CentOS 6. Take a look at CentOS Bug #6321 2. On Intel (and also AMD based) processor architectures, CentOS 6 requires PAE support for 32-bit x86 chips, following the upstream's requirement 3. Content for both the i386 and x86_64 architectures is split into two DVDs. All basic server and basic desktop installs only from DVD-1
Looking at the CPU HW specs it's a 64 bit (x86 compatible) CPU ... https://ark.intel.com/it/products/128984/Intel-Pentium-Silver-J5005-Processo...
it seems that your Intel processor is supported by Centos 6.x (and also 7 and 8...)
Centos 6.8 is quite OLD, so why don't you try at least the 6.10 release?
Have you got any issue installing/using that?
Give us some evidence of the problem you have so we can help specifically on that item
Cheers, Fleur