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Hhm, interesting. I don't normally use that Text and Font dialog, and instead just use the on-canvas controls. But with a little testing, I see that you have to actually type a character on the canvas, before that text field becomes activated. I'm not sure if that's a bug, or if there's some reason for it to work like that.
But in any case, with the Text tool enabled, click once on the canvas, and start typing. Once you type the first character on the canvas, the text field in the dialog becomes active, and then you can type into it. Or you can just type everything directly on the canvas.
Those instructions will create regular text. Inkscape also can make what it calls "flowed text". Flowed text really is only effective inside of Inkscape, so if you're going to save to a different extension, or view the document on the internet, the flowed text will have to be either converted to regular text, or converted to paths, to be viewed as you draw it. Why bother, you may ask? Because flowed text can be extremely useful.
Like for example, if you wanted to have a circle (or any enclosed space) filled with text, you can convert it to flowed text. Or if you drag out a box with the Text tool, and start typing in the box, you've made flowed text.
This is a little bit off topic, but I do wonder why Inkscape still has the Text and Font dialog. As far as I know, the only feature it provides, that you can't also do directly on the canvas, is setting your default font. Oooh, well now I have to take that back! There's a new tab in the dialog, since the last time I looked at it, "Variants". I don't immediately see how to use those options. So maybe it's part of a new feature that's not finished yet?
