Is it possible to make a drop down list with this formula?

Question

Google Sheets

I have formula

=A1-S2

in every line. I want to make the formula appear on click.

Answer 1

Right click on a cell: Data Validation .
Rules: Values ​​from the list
and write all your options there, separated by commas, for example:
=C1-B1,=C2-B2,=C3-B3
Demo table