Need Macro to copy and paste list of cells between to apps

My teacher grade book does not have a feature to copy and paste list of scores with hot key or cmd-v feature as one might do in a Google Sheet for example. Does anyone have a macro to share where I could select a column of data from an spreadsheet (which is then stored on the system clipboard) and then activate a hotkey and have KM paste one by one down the list the scores? Note: doing this manually one can press either tab or return key to move to the next cell below.
Thank you,

Hey Todd,

This depends upon your source spreadsheet.

What app is it?