Issue with creating a simple clock

I hope this is the right category.

I'm trying to create a simple app launcher as my first project, but it seems to be more complicated than it should be... My first task is to add a clock to the home screen.

I have tried connecting the upper text (reference below) to the currentTime global variable, but it doesn't seem to update. At first it does, but maybe currentTime is only updated once?

Also tried creating custom functions and actions but there's just too many restrictions, or I don't understand them.