How can I create a linked list that contains each folder with its files?

[ibreeden]

Well, that would work indeed, but how can a program manage to get the data from the folders in the path provided into that linked list?

Well, that is easy. You have done a good job. In line 24 (print(list_of_file_contents)) you have all the data you need.
So just after "# Main method" you add a line to create the dictionary:

the_linked_list = {}

... And after line "print(list_of_file_contents)" you fill the dictionary:

the_linked_list[path] = list_of_file_contents

That should do it. You don't need the lines after "# Get files and add directory to LL".
And again: this is not a "linked list", it is a dictionary.