A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
Hi Chas,
On the Structural Navigation, for the sub-sites, we can't delete them manually, but we can Hide them. If we don't want them to show up, just uncheck Show subsites under Structural Navigation. If we manually add some links to the navigation, we can delete them directly.
If that's not your situation, please share the details about how your created the links and share related screenshots with us.
Regards,
Felix