Depending on your model number for your notebook
there will be an HDMI and/or a VGA port off which you can connect a VGA or HDMI cable to your mobile computing device and run it to your monitor. Pressing "Windows" key + "P" will cycle through your secondary display features.
Might want to state the make and model number for your secondary monitor as well as the model number for your notebook which is an 8 digit number after your series number.