activate a member when a date arrives

Is there a specific time that the user needs to get activated? Or is it just 'on that day'?

You could use the task scheduler for these kind of things. Just use the daily() frequency and the task will get executed every day at midnight.

From there, it is just a matter of finding all users with a activation date of today and status is 0 and update their status.

Find the task scheduling docs here: https://laravel.com/docs/5.5/scheduling

@Thyrosis I want that the activation (status = 1) be executed automatically when activation_date much today date.

Then scheduling is your way forward. Something like this in the App\Console\Kernel file:

    protected function schedule(Schedule $schedule)
    {
        $schedule->call(function () {
            // There is a much better way to do this, but my brain doesn't want to cooperate today
            foreach (App\User::where('status', 0)->where('activation_date', { today })->get() as $user) {
                $user->update(['status' => 1]);
            }
        })->daily();
    }