You need to adjust the Page Order setting in the Brother Print Support App.
Fix: Open the app's Print Settings. Go to Layout > Multiple Page. Select your layout (e.g., 4-in-1). Below that, find 'Page Order'. Choose the correct sequence (Horizontal, Vertical, Horizontal Reverse, Vertical Reverse) for your document.
You can also add borders between pages. Use the 'Border Line' option in the same section.
If that didn't work, confirm you are using the Brother Print Support App and not the basic Windows driver. The standard driver does not support multi-page printing.
Heads up: The 'Collate' option in the Basic settings controls copy order, not page layout order. Keep Collate selected if you're printing multiple copies of a multi-page document.