In addition to Roel’s answer, there is also the Custom String module in the Marketplace that can display a String on a page directly from a Microflow.

I would save the string on a attribute of the enitity you are using on your page. When you write a text on a page (like 123) and you double click it, you can use the “edit” button on the “edit text” screen which opens the “edit caption” screen. Here you can add a parameter which is for example an attribute of the enitity you are using as a page parameter on your screen. You can use this parameter by replacing “123” by “{1}”. This will show the value of the entered parameter. 

Please mark this answer as accepted if this was helpful :)

Did you put a textbox on some page? You can give the text for the output as an attribute of the entity that belongs to the textbox.