SpongeBlob

Completely new to this so not sure what I'm missing. In photoshop I could change the fonts just by having the text layer selected and scrolling through the list of fonts that I have. That doesnt seem to work in Designer. After I've typed in something and press enter I get a layer with all the letters on separate layers under it and picking different fonts doesn't change anything. How do you change fonts after you've typed in something?