Ah, I see, when I read "I have to put my 100K thesis into a one page" I thought you had been asked to precis an existing thesis that you had produced (perhaps from a Masters, although I did think it impressively large!!).
In the case of a future thesis, well I would start by drawing up a very general plan for your 3 years (what you expect to achieve in each year) and then write a few sentences about the studies you plan to undertake. Obviously, you are not in a position (unless you have a crystal ball? ) to predict your results! Good luck with your PhD!