Website Built from spreadsheet template

I have a spreadsheet table that i need converting into a website with user logons, and put into a nice looking user interface. It basically uses a lot of the 'if' function, once figures entered it gives out a usable result, and a back office software to change the set data for different people. It is for hotel rate management and i need to be able to change hotel details like number of bedrooms and occupancy percentages, which the user wont be able to change, hence the back office softare part