Would this work?
setcookie("TestCookie", $value, time()+1;
So is this correct... from my understanding, you have to add the current time (since it counts from the epoch) and then add how many seconds? like one?
Yes, you are doing it right! time()+1 is completely valid.
Here is more information from the PHP manual about cookie expiration time:
This is a Unix timestamp so is in number of seconds since the epoch. In other words, you'll most likely set this with the time() function plus the number of seconds before you want it to expire. Or you might use mktime(). time()+60*60*24*30 will set the cookie to expire in 30 days. If set to 0, or omitted, the cookie will expire at the end of the session (when the browser closes).
But one (1) second is, as commented, a little bit too short to be useful.