Is the any API to send information?

I wanted to make a website there tells me how many players online, which map. What`s the players jobs and stuff
Its possible?

It is possible using the Source Engine Server Queries.

How do they work?

Open the link. All the documentation is there.

you’re better off not doing that ^

I assume you’ll have a website with PHP and some sort of data storage mechanism. So you can probably get away with sending a HTTP post of all the data you want to display (on mobile right now code is pseudo):

[lua]function UpdateWebsiteData() – run on a timer of 60 seconds or something
local postData = {}

postData['player_count'] = #player.GetAll()
for k, v in pairs(player.GetAll()) do
    postData['player_' .. k .. '_name'] = V:Nick()
    postData['player_' .. k .. '_job'] = v:GetJob()
    -- etc..
end

http.Post("your website.com/tracker.php", postData)

end[/lua]

Then read it and store it in tracker.php and display the stored data elsewhere on your site