Your text is already editable. If you want to change it, select the Type tool in Ae (Ctrl+T on Windows, Cmd+T on macOS) and then click into the text layer in the viewer panel, or double-click the text layer object in the viewer panel with the normal selection tool.
The “Convert to editable text” command in the layer context menu is for use with imported Photoshop layers. If you import a PSD as a composition, you can use the “Convert to editable text” command on the footage layers which contain text to create native text objects (that no longer refer to the source layer in the PSD). More here if you’re curious:
https://helpx.adobe.com/after-effects/using/creating-editing-text-layers.html#convert_text_from_photoshop_to_editable_text
Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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