Yes edit /etc/default/keyboard to set the global settings or ~/.dmrc for per-user settings.
Example /etc/default/keyboard:
XKBMODEL="pc105" XKBLAYOUT="fr,us" XKBVARIANT="oss" XKBOPTIONS="compose:ralt,terminate:ctrl_alt_bksp"
Example ~/.dmrc:
[Desktop] Language=de_DE.UTF-8 # change to your default lang Layout=de nodeadkeys # change to your keyboard layout
In either case, will need to also run:
sudo udevadm trigger --subsystem-match=input --action=change