Where to start learning js, basic functions?

Question

Programming

Good evening. I want to make a game, but I'm not familiar with js and need advice on where to start. I will learn it quickly, I am familiar with C ++ and php. There is understanding.
And here's what needs to be done.
The player selects the id of the action, the number of times this action (There is a limit, for example 3. You can repeat this action 3 times or 3 others, but one at a time) and the coordinates and presses the button (an event is sent, it is desirable that json arrives at the server).
Approximately this json should generate.

{
   "session": "session",
   "lastName": "id",
   "action": [{
       "id": "307",
       "count": "2",
       "location": 1011101
   },{
       "id": "1801",
       "count": "1",
       "location": 1011111
   }]
   "hash": "hash",
   "var1": true
}

I know how to write the server part in the trailer, html too) You can write in C ++ or take the php lumen framework, I think it will work)
In order not to learn all js now, tell me where to start. So to say the basis and that will help to realize all this. Maybe I can also take a frame, I'll make fewer mistakes .. And it makes sense to use websockets or ajax is enough?
Thank you for your understanding, and human thanks for the answers)
These are definitely events,

Answer 1

Tyk