How to Implement my CEILING formula?

Hello all,

My problem now is how to implement this formula in my documents.

I have formula: =CEILING(B2,0.05) to put limitations for my cell values,can i somehow put this (or similar) formula in my old documents.

If i do this now i going to lose my numbers,can formula be execute in the same cell somehow,this correct question.

if you know where i can read answer for my question would be very nice.