Random post with text

I made a new plugin, but i wanna do some more changes. I am not a develor, is someone to help my plugin to be much better of that?
The plugin page is https://blog.121416.co.cc/en/wordpress/wordpress-plugin-single-random-post-with-text/

I wanna make an automated refresh for div where the plugin make the work. I try to google for that function, i find some ajax codes, but i am not a develor and i cant understant how to aply the ajax to this plugin.