Mail of creation account or password initialization don’t go on gmail adress

Hello there,

I’m creating a website. And when I want to add an account (admin, or editor or whatever) on the backoffice, people who have gmail don’t receive the wordpress mail, or even the wordpress mail of re-initialization of the password.

But for an outlook or “orange” (i’m in France) mailbox, here it is working well even if it goes to the spam first.

Nothing on gmail mailbox nor spambox.

Is it a problem of smtp ? How can I solve this please ? Thank You