No, first you need to upload image on any public image host service like Photobucket:
http://photobucket.com/
When upload image you will get all codes you need for embed on web sites, forum or blog. Other option is to hot link it from any other site if this is public displayed. Right click on the image, from drop menu choose Image Address (location or what your browser give) and this info place in above mentioned box.
This forum also allow to user to direct upload images and for this you need to click on option Go Advanced when Post reply and find point Upload File...
This post goes much off topic... sorry
