How do I place several pictures next to each other, or around each other, and then save it like one picture?

You have to do that in a paint program. e.g. Paint Shop Pro.

The layman way to do it is to determine the size of the new picture based on the total size of the pictures you want to combine, make a new canvas and paste all the photos on that new canvas arranging them the way you like it... and merge and flatten them.

And save them as a new photo.

At least this is the way I do it:).....