Hi there tulip-flower,
And welcome to the forums!
It is not too hard to insert a picture gallery into a web page.
Galleria is a good choice: http://galleria.io/
It is well documented and very flexible / configurable.
Here are a few other gallery plugins (with demos) for you to look at: http://www.tripwiremagazine.com/2012/11/jquery-slider.html
If you prefer a pure CSS solution, check this out: http://speckyboy.com/2010/06/09/10-pure-css3-image-galleries-and-sliders/
If you have any trouble with the implementation, just let us know.