Windows Photo Viewer isn't part of Windows 10, but if you upgraded from Windows 7 or Windows 8.1, you might still have it. To check, press and hold (or right-click) a photo in File Explorer, and select Open with. If Windows Photo Viewer isn't in the list, you cannot install it on Windows 10.
- The Photos app in Windows 10 does the same things Photo Viewer did, and more..
Press Ctrl + the mouse wheel to zoom in or out. Change mouse wheel settings in More > Settings.
To browse photos within a folder, open a photo from the Folders view or File Explorer, then swipe right or use the arrow keys to see the next item.
- Click on a photo to show the buttons at the top, including Zoom, Delete, Rotate, Edit & Create, Share, and Print. Press and hold (or right-click) for more commands, such as File info, Save as, Copy, and Set as.
Open the Photos app from the button below.