To animate text for anything but scale, rotation and position, you need to add Text Animators. Pick any of the Text Animation presets from the Effects and Presets panel and then select the text layer and press the U key twice to reveal all the magic.
To randomly blink letters on and off you would add an opacity animator and then throw some randomness in the range selector values. There is a Text animation preset called Evaporate that will give you a starting point. You can find it by type eva in the Effects and Presets Panel:
This one animates Scale, Opacity, and Blur and looks like this in the timeline:
Learn more about animating text by typing Text in the Search Help field at the top right corner of the app:
You will find all kinds of resources. Adobe - Search: text. The help files and tutorials on Adobe TV will take you a long way to understanding the process of animating text.
When you have the text animating the way you want then make the text layer 3D and add a camera to the comp, then animate the Z position of the camera to slowly move in on your text or animate the z position of the text layer's Transform>Position property to move the text layer closer to the camera.