Can I create a client function in the server side?

Excuse me for any grammatical errors.

I would like to create a delay I created an opposite function but the function starts the delay for all. I don’t know if you are understanding, an example:

local delay = 10
local cansay = true
hook.Add("PlayerSay", "playersay", function( ply )
return cansay end)

local function startdelay()
cansay = false
timer.Simple(delay, function()
      cansay = true

This works, but it doesn’t work fine, because if somebody says something, then the delay starts for all!

Wrong section