Free Stock Photo Websites
Warning: Free stock websites will often have advertising from pay per use website. Often they will offer an image from such website and redirect you to a place where you have to purchase the rights.
Life of Pix
.Go to the menu >Explore > The Commons
Read over the rights
Make sure you are reading over the rights
Here is a video with all the advantages of the free stock websites, as well as limitations they may have.