You'll get the AWS S3 Integration settings in Settings > App Settings > Integration > AWS S3.

You need access key ID and secret access key to integrate. Please follow the steps below to get them:

Go to the AWS IAM console.

On the left navigation menu, choose Users.

Click on Create user button and fill as follows:

If you want to give full S3 access, do as below. But this is not recommended to give full S3 permission.

If you want to give access on a single bucket, click on Create policy button.

Add JSON data:

Copy the JSON data from below. Please remember to use your actual bucket name on your-bucket-name

{

    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:ListBucket",
                "s3:GetBucketLocation"
            ],
            "Resource": "arn:aws:s3:::your-bucket-name"
        },
        {
            "Effect": "Allow",
            "Action": [
                "s3:GetObject",
                "s3:PutObject",
                "s3:DeleteObject"
            ],
            "Resource": "arn:aws:s3:::your-bucket-name/*"
        }
    ]
}

Click on next button. 

Specify policy name and then click Create policy button.

Now come back to the Create user page again. Refresh the list and select the policy. Then click on Next button. 

Check the Review page and click Create user button.

Now your user is created. Go to the user details page.

Click on Security credentials tab. 

Scroll down and Create a new access key.

On step 2, add description tags if you want. 

And on step 3, you'll get the Access key and Secret access key. 

Add this credentials to the integration settings.

Add the Bucket name and Region then click on Save & authorize.

If everything is correct it'll show a success message and the status will be Authorized.

That's all! You've successfully integrated with AWS S3. Now all files will be uploaded into AWS S3.