DB query improvement for Notifications grouping

Hey All,

How can i optimize my below DB query and i also want paginated data.

$notifications = \App\Models\Notification::query()
        ->select(
            'notifications.*',
            \DB::raw('COUNT(*) as notifications_count'),
            \DB::raw('MAX(created_at) as max_created_at'),
            \DB::raw('(
                SELECT GROUP_CONCAT(
                    CONCAT(
                        u.echo_user_id, 
                        ":", u.first_name, " ", u.last_name,
                        ":", u.profile_pic,
                        ":", n.id
                    )
                    ORDER BY n.created_at DESC SEPARATOR "|"
                )
                FROM echo_users u
                INNER JOIN notifications n ON n.from_userid = u.echo_user_id
                WHERE FIND_IN_SET(n.id,  SUBSTRING_INDEX(GROUP_CONCAT(notifications.id ORDER BY notifications.created_at DESC), ",", 2)) > 0
                ORDER BY n.created_at DESC
                LIMIT 2
            ) AS latest_users')
        )
        ->where('to_userid', request('user_id', 557))
        ->groupBy(['notifications.to_userid', 'notifications.post_id', 'notifications.type', 'notifications.comment_id'])
        ->orderByRaw('max_created_at DESC') // Order by latest notification
        ->paginate(15);

    $notifications = $notifications->each(function ($notification) {

        $notification->users = collect(explode('|', $notification->latest_users ?? ''))->map(function ($userDetails) {
            [$echo_user_id, $full_name, $profile_pic] = explode(':', $userDetails);
            return (object) compact('echo_user_id', 'full_name', 'profile_pic');
        });

        $user = $notification->users->pluck('full_name');

        // Set the message based on the count
        if ($notification->notifications_count === 1) {
            $message = "{$user[0]} like your post.";
        } elseif ($notification->notifications_count === 2) {
            $message = "{$user[0]} and {$user[1]} likes your post.";
        } else {
            $totalNotifications = $notification->notifications_count - 1;
            $message = "{$user[0]} and {$totalNotifications} others likes your post.";
        }
        $notification->message = $message;
    });

Output: User A and 46 others likes your post.