As have metioned above, you can use VBA to do that, And I just find a macro may help.
Sub SaveEachPageAsADoc()
Dim objNewDoc As Document
Dim objDoc As Document
Dim nPageNumber As Integer
Dim strFolder As String
Dim objFileName As Range
' Initialization
Set objDoc = ActiveDocument
strFolder = InputBox("Enter folder path here: ")
' Copy each page in the document to paste it into a new one.
For nPageNumber = 1 To ActiveDocument.ComputeStatistics(wdStatisticPages)
Application.Browser.Target = wdBrowsePage
ActiveDocument.Bookmarks("\page").Range.Select
Selection.Copy
Set objNewDoc = Documents.Add
Selection.Paste
' Save new doc with the name of "Page" & nPageNumber and get the first 20 characters of the new doc as part of the file name.
Set objFileName = objNewDoc.Range(Start:=0, End:=20)
objNewDoc.SaveAs FileName:=strFolder & "\" & "Page " & nPageNumber & " " & objFileName & ".docx"
objNewDoc.Close
Application.Browser.Next
Next nPageNumber
End Sub
And I also attach the link in case you need more details.
https://www.datanumen.com/blogs/2-quick-ways-extract-individual-pages-word-document/
Good luck.
