How to use JavaScript i have this code but i don't know how to use it

[ThinhDinh]

If this is related to your previous post, please review this video again.

How to make column 2 - column 3 = column 4

You can use a Query column. The below video shows the general technique: https://www.loom.com/share/042be3be13004355b0dedec1be67b400