If you're going to use your own voice, you'll have to record the sounds, and then add them to the project as media. However, you have a 5MB cap so your samples should be the simplest, low level quality if you plan to have many. I suggest you read my tips below because you'll run into problems if your stuff is too large. Also, you'll need to use the Sound component to play the text recordings, as long as they're short.
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