@NickiA13 One way you could do this would be to create 3 different views of the document library. For example I have a document library with file names beginning A, B and C. So I created 3 views of the library with each one filtered by name begins with A etc. Then a document library web part has been added to each of the 3 columns on the SharePoint page. In each web part I have selected the appropriate view of the library and how many documents to display.
Intranet, SharePoint and Power Platform Manager (and classic 1967 Morris Traveller driver)