After you added index.html you want to open it and edit "IMAGELINKHERE", and "YOUR STUB LINK HERE", and put your links inside of them. Now upload your ImageLogger.html to a webhost such as https://000webhost.com/ now send the image you want to log people with through Discord and copy the link for that and paste it in "real discord link with image here".. and copy the website-link with your image and paste it below
Just like you send an image you want to link them your image-logger