1) Send the image you want to insert by a channel of discord as a file in any format (while supporting it and not very heavy there will be no problem).
2) Select the image you sent and copy the link from that file.
3) Paste the link in the article you type by selecting the image button or typing the link between the following command:
4) in preview mode, you can see it. If the image is large it will be seen surpassing both sides of the screen, but once the size is published it will adapt to the available margin, do not worry.
Note: It is advisable to create your own channel of discord to include all the images that you want to create link. For convenience, not to occupy other discords and because if the image disappears from the channel disappears from the article, leaving as a corrupt file.
Note: GIFs are also images, as long as they are not excessively heavy, they are also inserted in this way.