You will get this feature in both the free and premium versions.

• From the Appearance > Go to Customize > Theme Options > Blog Page.
• From the Blog Page, you will see the section for Drop Cap Option.
• Checked to Enable the Drop Cap. (It will help to make the first letter big on blog page posts)
• If the preview is fine, click on the save and publish button to save the changes.

Note: You will also get the same option inside Single Page Option in customizer. Please check.