Specs of AMD Athlon™ II X2 245 do clearly lack some x86_64-v2 features and first AMD CPU with all x86_64-v2 features is said to have been released in 2014. EL8 should be “fine” on the hardware though. (There would be no sight of LVM, if the SATA controller had no support.)
In other words, boot with el8 kernel fails (be it install media or other).
How is the Ironwolf “partitioned”?
lsblk -o name,size,type,fstype,mountpoint in CentOS should tell that.
The default would be two partitions, first with /boot and other a LVM PV that has LVs for
/, /home, and swap and whole disk allocated for these partitions/volumes.
Furthermore, default filesystem is XFS and one cannot shrink XFS volume.
One would have to boot with, for example, the CentOS 7 install media in order to erase. (I’d remove entries from partition table with fdisk and then write from /dev/zero to couple first megabytes with dd.)
If one wants to keep data, then one must have a backup first.
Presuming that the issue is with LVM detection, does the kernel have command-line parameter that would disable LVM detection on boot? The man dracut.cmdline says “yes”: rd.lvm=0
One can append that in bootloader, before the installer’s kernel boots.
Plan B could be to purchase a SSD drive, disconnect the HDD for the duration of the install, and install on SSD. There could still be the boot issue after HDD is reconnected (to act as data drive).