One possibility would be to install a terminal software.

The other one would be to connect with ssh to the emulator.
You could look up the ssh port in QtCreator (Tools-Options...-Sailfish OS-Emulator--SSH port).
Then create a ssh-rsa key and add it to the user authorized_keys. For the emulator you have following users: root and nemo.
The authorized_keys file for root is in sdkfolder/emulator/SFOSemuXXX/root/

If you added your ssh-rsa key to authorized_keys you could connect with ssh as root to localhost(127.0.0.1) port(2223) without password because of ssh-rsa key.