I'm taking an online class and trying to follow along with the instructor. He wants us to drop a clipart-style image into the page and change the color. It seems easy but all my images are on an opaque white background and all his are on transparent backgrounds. It feels like this should be easy to do, please help me.
What file type are your images? They will need to be png files for transparency. This is something you need to set up before bringing the images into XD as XD will only alter the appearance of the whole image through the Opacity slider.