添加并激活现有插件到您的自定义Wordpress主题

I have a custom Wordpress theme and I would like to ship it with an additional plugin and make it activated. I am very new to Wordpress and I have been looking at several resources online, but I am still unsure how to go about this. My understanding is that you would add in the functions.php the following:

register_activation_hook( __FILE__, 'the_plugin_I_want' );
function the_plugin_I_want(){
}

My question is how to I "embed" the plugin as part of the theme I am shipping without having the actual plugins (php and .js files) in my plugin folder in wordpress (wordpress\wp-content\plugins). Can I achieve this?

Thanks,

I.