Wacom software for MacOS High Sierra 10.13.6

I assume you mean the Wacom driver for tablets and so on?

https://www.wacom.com/en-us/support/product-support/drivers

Go to the older versions link under macOS and find the one you need - likely Driver 6.3.44-2 (macOS 10.13 - 12). Although, depending on which device you have, it may not accept such an older driver.

You probably also want to read this - https://support.wacom.com/hc/en-us/articles/4411693955095-Setting-up-the-Wacom-driver-with-macOS

There’s no workaround for this. You’ll have to buy a newer Mac, one that can run macOS 13 Ventura or newer.

High Sierra has long been outdated and unsupported.