specific .htaccess permissions?

Trying to get this running. As far as I can tell, I’ve given the .htaccess file the permissions the plugin needs, but it still complains it can’t write to .htaccess.

Can you please be specific in the installation instructions (1) which .htaccess files need permissions (root or just WP root or what) and (2) the specific permission settings required? Also, given that this plugin says it adapts as Jetpack changes its IP block, does the .htaccess need to be permanently set for these permissions, rather than just during the installation of your plugin?

Thanks.

https://ww.wp.xz.cn/plugins/stop-xmlrpc-attack/