Q2A generate Meta description dynamically and SEO friendly as per your page. Keywords I think it is not so effective see this http://googlewebmastercentral.blogspot.com/2009/09/google-does-not-use-keywords-meta-tag.html
Still if you want to add into the theme file you can overreide head_metas() method. (see in qa-include/qa-theme-base.php around line no#244
Welcome to the Q&A site for Question2Answer.
If you have a question about Q2A, please ask in English.
To report a bug, please create a new issue on Github or ask a question here with the bug tag.
If you just want to try Q2A, please use the demo site.