How to open whats App in your PC/Laptop

First to you check connection of your mobile 

Note:-Internet connection in your mobile is necessary

Go to google and search whats app web
https://web.whatsapp.com/

Open Whatsapp on your mobile
Select 3 dots on right panel
Select Whatsapp web.
Scan Code with your PC /Laptop .
After a little time Whatsapp will open in your PC /Laptop .
Now you are able to see your whatsapp message on PC/Laptop.