Press the green flag and then press the arrows to scroll the cards. Click with the mouse pointer and hold it, and you can move it around to view the stuff up closer. I may use these cards in a card game later but right now I'm too busy making things on Tinkercad.
The cards do have outlines they're just black so you cannot see them in the black backdrop. Credits: Thanks to Kingman_III for the original project AUTOMATIC Pixel Showcase Engine. Check him out, his stuff is cool!