Put the picture link to the guide and the picture will be shown when you save the changes
The site uses a combination of BBCode and markdown if I recall correctly. Should be plenty of guides available for this sort of stuff if you need anything else (or clarification),
Idk if i do it correctly but the pic isnt show https://www.speedrun.com/Dashy_Crashy/guide/8clsp
pretty sure you don't understand what direct link means...
use the .png link
https: // i.imgur.com / CIKIjxK.png
if the image is on your PC, upload it somewhere (imgur or other website) get the image link post the link submit reply / post done
Right click > "Open image in new tab" > Copy the image link
You know what to do then
On imgur, click on the image you want to use and click on "Direct Link" and it should copy the right link, then just paste it exactly like that on here.