How to share images in Zoom meetings showing only the image?

Solution 1) A professional solution is to insert your images in a powerpoint or similar presentation software. First start the presentation, then share the presentation in Zoom.

Solution 2) Only using Zoom and any photo software, you can go on "share screen -> advanced -> portion of screen", so you can select exactly what you want to share. Be careful as this will capture independently of the application any window(s) which is in the foreground. Zoom will remember the position of the shared portion between subsequent shares, even in different meetings, so you can start an empty meeting and set up your screen, close that meeting and only then enter the meeting in which you want to share your images.