Add javascript function to my website

for my websiste (please consult attachments)

Usage of the website :
Users will fill some field with « cheval name » to display points and rank

Instructions for development :

1/insert a column (name named) between # and Cheval with for content the number of the line :
In this screenshot, result will be 1 for the first line, 2 for the second line until the 16st line

2/at the right of the button « Ajouter une ligne », add un button to export result display in xlsx and csv format

Thanks !