To put two images together in Photoshop, you will need to use the “paste” command. To paste one image into the top left corner of the other image, hold down the control key and click on the first image. To paste the second image into the top right corner of the first image, hold down the control key and click on the second image.
To put two pictures side by side, you will need to use a photo editor such as Adobe Photoshop or Picasa. Once you have edited the photos so that they are of equal size, then you can place them next to each other using a photo frame or photo album.
To merge three photos in Photoshop, you can use the Merge Photo dialog box. The Merge Photo dialog box is located in the Image menu of the Photoshop window. In the Merge Photo dialog box, you can select one of the photos to be the source photo and choose another photo as the destination photo.