When you enter your theme editor, and add section, "carousel" It will be first displayed as this, with section on the left, your work board in the center and and the settings on the right side bar.

To maintain high resolution images, please make sure your images are around 1260 px by 720 px for best results.

Here you will see that we have attached an image at the very top of the settings.

Overlay color means the color overlay you choose to have overlaying your whole image.
The opacity is the clarify of the image to help increase or decrease legibility.

If you want to blur your images, you may with the blur settings, which blurs the entire image, scaling from 1-20. This can help emphasizing your heading text and call to action button.

Under the captions segment, you can choose the positioning of the caption, center or bottom of the image.

Place a heading line in the title and you have the option to choose the title size by selecting H1-H6. These are heading sizes.

The description is where you would add a subtitle. as in the image provided in the example. Description size options is the same logic as the title sizes, fs-1- fs-6, 6 being the smallest.

BUtton text is where you would type your call to action button and the button URL is where you want it to go to.
From there, you have button color and button size options. These colors are based on the colors you have chosen in your theme settings, in the colors section.