Templates are created in WebEasy just the same was as creating a normal web site. All you have to do is use the "Save As -> Template" option to save your site as a template.
Solution
1) Create a site in WebEasy.
2) Go to the "File" menu and select "Save As -> Template".
3) Make sure you are in the WebEasy Templates folder, enter a name for the template and click "Save".
Now when you create a new site, or insert a page into an existing site, you will be able to select this template.