We are migrating an SP 2013 site to SPO. The customer has article pages where the page has the logo, headings, subheading, article tagging, article contents ( with HTML formatting) and these data contents get saved in the content type of the Pages library. So migration was easy via reading the data contents from its content type. Now to achieve the same business requirement, we are able to build a modern article page that replicates the existing business requirement. But we are not finding options to save the data back in the content type of the Pages library that keeps the data intact. The article page should have a unique URL same as a normal SharePoint page so that it can be used in user search, tagging, etc, which was limiting the SPFX based solutions for this.
Please help with some solutions/suggestions to save the data content of the modern page in the content type.