To change the Featured Image Settings in the blog page. Go to Appereance-> Basic Settings -> Blog Settings -> Featured Images and choose any one options. You can choose wide featured image as well as small featured image on your blog pages.
Wide Featured Images
Wide Featured Images enables you to display full width featured images on the blog pages.
Small Featured Images
Small Featured Images enables you to display Small width featured images on the blog pages, the content will be aligned with the images on the left side.
How to hide the Featured Images on the Single Post View
In this theme you can hide the featured images on the Single Post View. To do so Go to Appereance->Basic Settings->Blog Settings->Featured Images-> Hide Full Post Featured Image.