Apple has done a good job on the implementation and documentation for their confidential computing (https://security.apple.com/documentation/private-cloud-compu...) but of course it’s Apple only. There’s a few folks working on a non-Apple version of this, eg https://confident.security/ and others (disclaimer that I helped work on a very early version of this.

Read the Apple docs - they are very well written and accessible for the average HN reader.