To make the Joomla generated order of articles listed on a “Category List Layout” page or “Category Blog Layout” page be the same as the numeric order of articles in the category, log in to the Joomla administrator then click on "Menus" then click on the desired menu name. The Menu Item Manager for that menu will appear. Click on the desired menu item. Click on "Parameters (Advanced)” near the right center of the page. Change the "Primary Order" from "Default" to "Order". Click the "Save" icon near the top right to make the change stick. Refresh the page in the front end and click on the menu item to verify the change worked as you expected.
I also recommend you set the following options in "Parameters (Basic). Change the "# Links" to "All" and set "Filter" to "Hide" unless you have an unusually large number of articles in that category.
