Hello, had the same question, after this forum which helped me, but not at 100% ;-) I found this hint for the help button (here in Bold):
"
Language test result form or certificate number (see help button for Language test taken) (required)"
on that button the following text pops up and answers my question.
"
Help - Language test taken
For IRCC to verify your language test results, you must:
- IELTS: Enter the Test Report Form Number only (it is at the bottom right corner of the page).
- CELPIP: Enter the Registration number.
- TEF: Enter the first part of the attestation number without the hyphen. This number is made up of two sets of digits separated by a hyphen. It is at the bottom of the first page of the test.
- If you have a TEF attestation that has two score columns, please enter the scores from the "Équivalence ancien score" column.
- TCF: Enter the last 7 digits of the candidate code
For the language test PIN, you must:
- CELPIP: Enter the 6-digit PIN number.
- TEF: Enter the second part of the Attestation Number - the 7 digits that follow the hyphen. The Attestation Number is at the bottom of the first page of the test.
"
have a nice day!