Hello,
To add borders to the footer areas you need to create an HTML block for the footer and add all the elements in it.
Then you can assign a border to each row from design options.
Screenshot for Clarification: https://ibb.co/GTz81rL
Then you need to make the footer single column and assign the html block to the footer.
Screenshots for Clarification: https://ibb.co/fD053fM
https://ibb.co/0f3LSZH
For the prefooter section you need to edit the HTML block used in the prefooter area and from Theme Settings >> Footer >> Prefooter text.
Screenshot for Clarification: https://ibb.co/QH2XHfJ
And add the border to the row as mentioned above.
Best Regards.