There are actually many different ways to do this. You can use programs to create presentations, edit photo slideshows using online extensions in the browser, select the appropriate settings on the camera to get a series of photos that can be easily converted into gifs. In the end, you can set up automatic image changing in the gallery of your PC or laptop and use tools that record the screen, for example, here https://www.movavi.com/screen-recorder/ is description of one of such programs. These are really effective solutions for those who don't have any skills and knowledges to work with professional photo and video editors.