Before you can do anything else (such as compile) a C program with the IDE you must load the file into an IDE edit window. These are very like Notepad: they provide basic text editing facilities.
To open an edit window, and load WOTCOST.C into it, drop down the File menu and select the Open menu item. This will bring up a file selection dialog box, quite similar to (though also slightly different from) a conventional Windows file selection dialog. You should be able to use this to select WOTCOST.C. An edit window will be opened. You should be able to see the text of WOTCOST.C. If you cannot do this, then ask for help from the demonstrator.
Once you have an IDE edit window successfully opened, experiment with editing the text, saving it, closing the edit window, and reopening it.
It is possible to have several edit windows open
simultaneously. Each normally accesses a separate
file.
The name of the file being accessed or edited is shown in the
title bar of each edit window.