A great place to start is the book by Evans, "
Rocket Mass Heaters." And read everything Ernie and Erica Wisner have posted here (they are soon to release a book too, and I expect that will be well worth reading too).
Your question suggests you have a great deal of reading ahead of you this summer. You have a couple good months in the summer to read everything you can find.
And I highly recommend beginning with an outdoor build, just like you are planning. We never want the
rocket stove to burn itself down, but if that's what we're going to do, far better for that to be outside in the garden!
What you describe will not work. I suspect the fire riser would burn itself out, and then the heat circulation would fail. Then the fire would either become smothered, or just burn like a small fire built in the feed tube. Not terrible if outside. At best super nasty/smokey if inside, and potentially far more dangerous. Always test outside first, and be prepared to put out the fire if it gets out of control.
