Write macros for Excel

You need to write a macro for Excel. A base of enterprises to control the work of managers.
- macro, which will change the color of the filling of the cell depending on the elapsed time from the date of filling the cell
- Closing the possibility of making changes to the cell after the data is entered
- differentiation of visible businesses for each manager (the manager enters under his password and sees only his enterprises)
- training 1 person to maintain this base, with the subsequent need to make additions and changes