You unfortunately can't upload pictures directly on the website, both due to how easy it is to have troll users adding content that might not be removed in time if it's explicit, for example, and also since images are what takes up a server's space the most, but I recommend you either create a blogger and use it as a personal storage blog (what I did my entire life and how I was able to bring the website back through 2010-2012 screenshots I took!

) or imgur, imgur is free and you don't even need to sign up, besides being very globally used. Just click in upload, drop your pic and you're all set!
https://imgur.com/upload 