The RHEL 7 / CentOS 7 comes with systemd (System Management Daemon) which is a init system uses target instade of Runlevel Numbers but the concept is same.
To List all active units/services just run the below command.
# systemctl list-units
Or you can filter the unit list to find targets by using the below command.
# systemctl list-units --type=target
To check currently system is running in which Runlevel by using below command.
# systemctl get-default
Here currently I am in Graphical User Interface (GUI) or Runlevel No. 5. Also you can use the below command to check the current Runlevel.
To Switch the Runlevel to Text mode use the below command.
# systemctl set-default multi-user.target
If you want to switch to GUI from Text Mode you can use the below command.
# systemctl set-default graphical.target