I am trying to apply my XML template to my site on Sharepoint, and I keep getting this warning:
WARNING: The source site from which the template was generated had a base template ID value of SITEPAGEPUBLISHING#0,
while the current target site has a base template ID value of STS#0. This could cause potential issues while applying
the template.
Do you guys have any idea how this can be fixed?
The warning is present because the source site from which you extracted the template is a Modern Communication site whereas the destination on which you are applying template is a classic team site.
This is a warning message not an error. If you apply the template on a Modern Communication site, this warning will not appear. It is a warning to you that there is mismatch between the source and destination site base templates.