If you want to change the size of the file that Joomla will upload when you post a new article, first make sure you have the correct file extension for the file you want to change. To do this, open the Settings menu (in the upper left corner of the main screen), and then click on the Files category. In the Files category, on the right side of the screen, you’ll see a list of file types. The file type you need to change is called .php. If you’re posting an article in .txt format, you don’t need to change anything.
jpg format, you’ll need to change the file extension to .jpg. After you’ve changed the file extension, click on the Upload Files button, and then select the file you want to upload. In the File Size field, enter the new size in bytes, and then click on the Save Changes button. After you’ve saved the changes, your new file size will be applied to future posts in .jpg format.