How to implement cache-control and pragma http header set?

This is something you should ideally do directly in your web server software, not in WordPress. Here’s a short tutorial I found to set cache-control: https://wpthinker.com/how-to-set-cache-control-header-in-wordpress/

If you really want to use WordPress, here’s a plugin that can set these (and many other HTTP headers): https://ww.wp.xz.cn/plugins/http-headers/