Hi @Max Johnson,
Thank you for posting in this community.
We regret that it is difficult for us to copy pages from the parent site to the subsite.
The reason for this difficulty is that the content of the parent site is separate from the content of the subsite.
For example, an image that you uploaded to a page on the parent site is stored in the parent site's Site Asset library, and the child site's Site Assets library does not store that image.
Some web parts of the page are also saved by the parent site. And for the sake of file security, the child site cannot directly access or share the content of the parent site (in case some users who can only access the child site can see the content of the parent site).
If you really need to copy pages from the parent site to the subsite, then I am afraid you will need to copy all the content involved in the parent site's pages to the child site first before the child site creates the same pages.
Thank you for your kind understanding.
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