Digital Picture Frames

Does anyone know how to put pictures into a Digital Picture Frame?
I just bought digital Picture Frames for my mom and I can’t figure out how to get the pictures in there. Do I need an extra memory card ? How do I get the pictures off my computer and into the frame? Is there a frame someone could recommend that I could just load my chosen photos off of my computer to put in the frame?
i think you need a flash drive/thumb drive. i saw in a shop where they used a flash drive
KODAK 8″ and 10″ Wireless Digital Picture Frames