I am planning a 30 mile walk a day for two days. is this physically possible and what can i do to keep myself healthy?

Make sure to keep: Yourself well hydrated.

Prepare yourself: Besides staying well hydrated as other doctor noted, also prepare yourself for such physical exertion. If you have been a couch potato, walking an avg of 15 mi/day is taxing. Also be sure to stretch properly, wear appropriate shoes, and rest accordingly. Do not try to break in a pair of new shoe at the start of your walk. Bring bandage in case of blisters and proper sole support. Have fun