To ensure consistency, single images should be inserted using the standard WordPress image block. If the image exists on Wikimedia Commons, then that’s what should be linked to rather than uploading the image to the Engole media library.
Image captions should be inserted using the [caption] shortcode, which takes one optional parameter, the source to be attributed. By default, attribution will be to Wikimedia Commons.
[caption]This is a caption[/caption]
To attribute to other than Wikimedia commons:
[caption]This is a caption|YouTube[/caption]
Leave the attribution parameter blank:
[caption]This is a caption|[/caption]
|Ernest Boulton, also known as Stella|
Double images can be inserted using the Advanced Gutenberg Table block, as here. The easiest way to insert your own is to go to the code editor and copy this code into your own article, changing the images, titles and captions as appropriate