You’ll have to use another program to create the text. If you’re just looking to engrave after cutting out the phone shape you can use something like Microsoft Powerpoint to create text, then copy/paste into the GF App. Make sure to use “Set Focus” before placing your text.
You’re really going to need to learn some graphics software to get the most out of your machine. Whatever you choose, you’ll find a lot of people here willing and happy to help when you run into problems.
Inkscape is free, and there are plenty of tutorials in the Tips and Tricks section.
If you want something cheap there is the Affinity programs: Designer and Photo (they’re on sale now). The are pretty functional.
I’m using the Adobe Creative Suite which has a monthly fee.
There are other options as well.
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