Hello killertomato,
As optodata pointed out, the Help file is a good place to start.
In the Edit module, there are quite a few tools & it may be difficult to navigate at first.
You can use the
Shape tool to add a shape, then resize & reposition it and adjust properties like opacity.
You can re-order layers simply by dragging & dropping (e.g. to move the background shape under the text layer)
PIX
PIX YouTube channel