Linking between two Apple Notes should work. See link to Metadata [applenotes:note/a7c3a7df-242f-42e6-b62a-4399b0575d0f?ownerIdentifier=_eb06fcf84638b248e9eebdf1eb7b3c67] note.
Use native Apple Notes links. For that just type ">>" and you would be able to select a link.
Another link to Code highlighting [applenotes:note/6e60eca8-b390-4efe-b515-3898416bca20?ownerIdentifier=_eb06fcf84638b248e9eebdf1eb7b3c67].
Here is how links should look in your Apple Note.