If are planning to immigrate to Canada through Express Entry, you will have to prove that you can communicate in at least one of Canada’s official languages, either English or French.
To demonstrate your proficiency in French on your Express Entry profile, you must take either the Test d’évaluation de français (TEF) or the Test de connaissance du français (TCF). Demonstrating your French proficiency can provide you with several advantages in the Express Entry system.
All immigrants applying through the Express Entry system must demonstrate proficiency in either English or French. To do so, they must take a French language test approved by Immigration, Refugee, Citizenship Canada (IRCC).
https://www.canadim.com/blog/the-tef-exam/