You can create nested menus in Bitrix24 Knowledge Base by creating a standard menu and dragging the menu items.

Create a standard menu

To add a new menu, click Add block > Sidebar and select a suitable vertical menu.

Then click the cogwheel button > edit.

If it's a new menu, remove menu items that you don't need and add new ones by clicking the + button.

When you use this method of adding menu items, the Knowledge Base page for this menu item is generated automatically.

You can also add menu items by clicking the New page button, but this method can be used if you need to create a standard menu. To create a nested menu, you'll have to edit the menu.

Create a nested menu

To create a nested menu, you need to create a standard menu item and drag it where you want it.

You can also change the order of menu items: