There is a permanent thread in the Help Center, right at the top of the page, describing how to post pictures. Have you read that yet?
Also - 98% of the time when people have problems posting pictures, it will be because the picture is too big. Since you have obviously never posted a picture, it's very likely "how do I resize this?" will be your next question. This is why people were trying to help you with resizing, also. No need to be brusque.
Last edited by Peckish; 11-24-2019 at 02:52 PM.