In latest update, WordPress now provides – Block Editor – for widget too. It is just like WP Post Editor.

• Go To : Appearance > Widgets.



• Select the – Widget Area – where you need to add widget.



• Click – Add Block
• Find – Custom Widgets and all other widgets under – WIDGETS



• Click on the widget you need to add to sidebar



• It will get added to that sidebar at the bottom
• You can drag and re-arrange widgets as per requirement just like we do in WP Block Post Editor.