It sounds like you're referring to folder thumbnails.
Windows 10 provides a multi-picture folder thumbnail. Windows 11 provides a single, half-covered folder thumbnail. There is no option to get the Windows 10 style folder thumbnails in Windows 11.
I've written some free tools that provide an alternative folder thumbnail display, but not the Windows 10 style:
FolderThumbNailFix will change the Windows 11 folder thumbnail from half-covered to full size. Note that this fix must be reapplied after any major Windows update and should only be used on personally owned computers (i.e. not your employer's computer).
The Folder Options tool within Right-Click Tools will let you set large folder thumbnails that can be a single image, 2 landscape, 2 portrait, or 4 up.
Note: I do NOT work for Microsoft. I just write some free software and sometimes answer questions here.