How to make a selection function in a cell?

Question

excel

Hello. How do you make a selection in excel?
?
The other day I downloaded a cool table on the introduction of habits. Every day you mark YES or NO, and depending on the answer, the total number of points increases or decreases. It turns out in an ex-fur-tree it is possible to create similarity of variables and to set to them value?
Tell me where to dig, otherwise the sheets of the file are protected from editing, I can’t see the formulas.

Answer 1

1. You select the cells in which you want to create a list.
2. Data > Data Validation
3. Select the data type "List"
4. Specify the source (a range of cells with the desired values ​​for the list)

Answer 2

This is not a formula, but a selection condition. I can’t tell from memory, but it seems that there is such an item in the cell settings (in the context menu). There you can choose from a range or enter options with pens