The order of articles on your site isn't something you configure in the console — it simply mirrors Notion. Within each collection (and each sub collection), articles appear in exactly the order their pages sit on the parent page. The same is true one level up: collections follow their order on the root page.
So if your articles are out of sequence, fix it at the source. Open the collection page in Notion and drag the article pages into the order you want, top to bottom. This also reorders the groups and entries in the Documentation layout's sidebar, since it's built from the same tree.
Once you're happy with the arrangement, open Settings → Help Centers and press Resync — the new order goes live right away. No extra settings needed; Notion's order is always the source of truth.