Thanks for this report. Assuming that this is a reasonably recent installation of Endless OS where you selected AZERTY during the initial setup process, this is a known issue. Try editing the file /etc/default/keyboard
to contain the following:
XKBLAYOUT=fr
XKBVARIANT=
You can do this with a command like this:
( echo XKBLAYOUT=fr ; echo XKBVARIANT= ) | sudo tee /etc/default/keyboard
entering your password when prompted.
Then restart the computer.