White background behind PNG for asset manager?


Im pretty new to this, but maybe someone here can help.

I’m just experimenting making an product manager, and i’m able to load in images from a file and use as a product image. If i click it, the product loads in.
But I was wondering if its possible to make the background white by default, even if there is a png with a transparent background as the product image?

Like this basically. You can see the image on the left has a white background already, but the one on the right is using the default colour and is transparent.

Is there some way to add a white bg behind? Maybe load in a white image and then load in the product image over the top?