But how do you import from a Google document or a .docx file?

A few months ago I backed up my TO tree and I must have saved as a plain html document. Now when I open the document I can only import one link at a time.  I also tried selecting the entire document and dragging but everything gets moved as one link.  I have hundreds of saved links is there a way to import the entire tree from the plain HTML or convert the plain html to complete html?  I also have the tree saved as a .doc file if it’s easier to import that way.