systemctl

$ systemctl get-default                                         #show current default target for UI(Gnome or another UI)

$ systemctl set-default graphical.target               #set gui instead cli (change runlevel from 3 to 5)

or

rm '/etc/systemd/system/default.target'

ln -s /usr/lib/systemd/system/graphical.target   /etc/systemd/system/default.target