Before you are able to edit a course in Moodle first login (http://courses.unic.ac.cy/) and open the specific course.
When you load a course you only are able to view what has been added to it. In order to edit the content, click the gear icon 
and then Turn editing on button.
Edit Mode located on the top right corner of the course.
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After you turn editing on Edit Mode all edit menus and other options become available to you in the course, and the Turn editing on changes to Turn editing off.
To select the specific Activity/Resource to be added to the course, click Edit Mode is red to indicate it's on.
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To add an Activity of Resource to your course, click on the Add an activity or resource (4) at the bottom of the specific Week or Topic section. option that is available under each section(General, Week 1, Week 2 etc) in your course.
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This will load the Add an activity or resource menu.
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To add an activity or resource from this menu will display a description of it on the right panel. After making a selection, click Add to load the setting for it to be added to the coursejust click on the icon you like. Then just follow the instructions indicated in the activity or resource.
If you want to see more information regarding the activity before adding it to the course you can click on the "i" below each icon.