When raising a pull request for a terraform code i.e. , you sometimes need to attach a plan to describe the changes the code is going to make, it s mandatory for the review/approval of your PR 

a common use for a devops is a terraformf plan you attach to the PR

On your PR , you click on that add file button in the comment section,

it ll open the explorer to let you navigate to your file and select it( you can select multiple files) , then click on open

it ll show you it s updating, and then list all the files you ve selected

And it ll show like this to the reviewer, who can then consult it and leave his review