Go to Facebook developers site
For example, the Like Plugin
Generate the code. You'll get the generated code back in 2 blocks. The first is the SDK that must be added once on your page... preferably after the opening
<body> tag. Depending on your theme you can paste that directly into header.php. If you have a child theme you might do it with hooks and filters... I can't say.
Then Facebook says to place the second part of your code wherever you'd like it to appear, so in your case directly in your page template. You might even be able get away with pasting both sections of code directly into your page template.
There are a lot of plugins in the plugin repository that deal with Facebook if you aren't comfortable with code.