windows & Wamp solution:
1. go to "https://curl.se/docs/caextract.html" and download "cacert.pem"
2. Put it in this directory "C:\wamp64\cacert.pem"
3. go to "C:\wamp64\bin\php\YOUR_PHP_VERSION\php.ini" and put those two lines:	- curl.cainfo = "C:\wamp64\cacert.pem" - openssl.cafile="C:\wamp64\cacert.pem"

This is just what works for me and I am writing just to remind me what I have
done when I will forget what I have done.
If it doesn't work I am sure you're going to find the solution
windows + Xampp solution:
1. go to "https://curl.se/docs/caextract.html" and download "cacert.pem"
2. Put it in this directory "C:\xampp\php\extras\ssl\cacert.pem"
3. go to "C:\PHP\php.ini" and put those two lines:	- curl.cainfo = "C:\xampp\php\extras\ssl\cacert.pem" - openssl.cafile="C:\xampp\php\extras\ssl\cacert.pem"

All of the answers are correct ; but the most important thing is You have to find the right php.ini file. check this command in cmd " php --ini " is not the right answer for finding the right php.ini file.
if you edit
curl.cainfo ="PATH/cacert.pem"
and check
var_dump(openssl_get_cert_locations());
then curl.cainfo should have a value. if not then that's not right php.ini file;
*I recommend you to search *.ini in wamp/bin or xxamp/bin or any server you use and change them one by one and check it. *

//in laravel/config/filesystems.php
//add this line in S3
'scheme' => 'http' // to disable SSL verification on local development
//Your filesystem.php should look like this
's3' => [ 'driver' => 's3', 'key' => env('AWS_ACCESS_KEY_ID'), 'secret' => env('AWS_SECRET_ACCESS_KEY'), 'region' => env('AWS_DEFAULT_REGION'), 'bucket' => env('AWS_BUCKET'), 'url' => env('AWS_URL'), 'scheme' => 'http' // to disable SSL verification on local development
],
//When you run it on your server which has SSL verification, you need to comment 'scheme' line.