i thought that i am allowed to move around characters however i want

This is basically what "rearrange" means. If tests are failing for you, then most probably you do not check for rearrangements correctly. One potentially tricky case: scramble('a', 'aa') should return False.

The key is in this part:

1 item per page: page_item_count

That method returns how many items per page are in a certain page.

Using list [1, 2, 3, 4] and page length 1:

Page index 0: [1] ; count = 1
Page index 1: [2] ; count = 1
...
Page index 3: ???

not an issue. Read the description with more attention, please. The discourse is not here for you steaming out some frustration.

4, it is explained in the kata description.

the count of distinct case-insensitive alphabetic characters and numeric digits

"aabBcde" -> 2 # 'a' occurs twice and 'b' twice (`b` and `B`)