Setxkbmap is a tool to set the keyboard layout. In the options of the tool you're allowed to set a switch.
setxkbmap -option grp:switch,grp:alt_shift_toggle,grp_led:scroll be,us
sets the keyboard to belgium (be) and with alt+shift I can switch to a us layout.
You can find the explanation for the coding in:
/usr/share/X11/xkb/rules/xorg.lst
You might want to execute this command autocratically on login, so you don't have to type it all the time again.
create a file "setxkbmap.desktop" in "~/.config/autostart/"
nano ~/.config/autostart/setxkbmap.desktop
and enter the setxkbmap command
[Desktop Entry] Encoding=UTF-8 Name=sertxkbmap GenericName=set keyboard layout Comment=Switch with alt+shift the layout of your keyboard Exec=setxkbmap -option grp:switch,grp:alt_shift_toggle,grp_led:scroll be,us
this file will be run every time you login to your system
