Robots Txt File?

I have the following in my robots.txt file. Where is the sitemap.xml located at? Or do I have to make one?

User-agent: *
Disallow: /app/
Disallow: /store_closed.html
Disallow: /admin.php
Disallow: /var/
Disallow: /js/
Disallow: /config.php
Disallow: /config.local.php
Disallow: /?currency=
Disallow: /index.php?dispatch=
Sitemap: not sure what to put here.

IS this good? anything else I am missing? also when I edited robots.txt in admin no longer on my dir root?

I have the following in my robots.txt file. Where is the sitemap.xml located at? Or do I have to make one?

You can add the following lines to this file

Sitemap: https://www.domain.com/sitemap.xml
Host: https://www.domain.com

I don't think it is a good idea showing following:

Disallow: /admin.php

Disallow: /config.php
Disallow: /config.local.php

Robot.txt is a public file