1 - Click on "Custom size" and create a new design 1080x1080 px
2 - Drag your book cover to Canva and resize as you like
3 - With the cover selected, click on "Effects" and in "Shadows" options choose "Drop"
4 - Click again on the "Drop" shadow to open the adjustments option
5 - Download your image
✨ Yay! Done!