Hello,
I saw the screenshots you attached the html blocks come with demo import. So to import only the HTML Blocks as in the screenshot.
You need to do it manually. You need to paste the code from the files one by one by adding a new HTML block and save.
You need to follow the steps as in the screenshot.
Screenshot for Clarification: https://ibb.co/cNSs6cS
You can download the files from the link below:
https://jmp.sh/AQSFhL5
Note: The Images will not be imported in the way mentioned above.
If you don’t want to do it manually then you can import the complete base import then all the elements will be imported.
Best Regards.