Thank you so much for using AcmeBlog theme. As per your question, if you want to remove the No Image Available, please add the featured image on that post where you want to remove it. In case of Pro theme, you can set your own default no image available. If you missed to add featured image, default no image available will appear.
If you want to remove the category on that page, you need to customize the theme.
Find that codes on theme file and customize as your need.
Note: Child theme is recommended to customize theme.