Hello

There is a way indeed. You need to use the Tools/Protection/Protect sheet (or workbook) option. This will then prevent anyone changing anything.

In order to hide the formulae you need to select the cell in question and under the Format/Cells/Protection select "hidden". This means that when you protect the worksheet the formula will be hidden. Even though it is invisible it can still be deleted so you shoudl also check the "locked" option next to the "hidden" option and then people will not be able to change anything either.

By default, every cell is set up with "Locked" in a speadsheet so that when you activate protection nothing may be changed. If you need to allow input into certain cells by the user then you should select those cells and uncheck the "locked" option. Of course if you want someone to be able to enter in more cells than not then you can select the whole sheet, deselect "locked" for everything and then simply reselct "locked" for the few cells in question.

Clear?

Good luck