How to make a notification on node.js?

Question

Node.js

Guys help, you need to make a notification as in VK for messages (if you have written a message, you have "+1" displayed). I need to do the same only for orders. If you have been added to the list of order executors, then you can see it on your profile (for example, a bell icon with a one). I have no experience with socket, so please. I will be very grateful.