Hi @vadim V,
I hope you are well today and thank you for your question.
This The Google+ plugin plugin lets you add a +1 button to your website so that people can tell the world how awesome they think you are. It integrates with Google+ Posts and Pages so that people can easily add you to their G+ Circles.
You can also post directly from G+ to your WordPress website using this plugin.
The plugin doesn’t provide functionality to log in WordPress using Google Plus.
You can use any of the following plugins to achieve it.
https://ww.wp.xz.cn/plugins/google-apps-login/
https://ww.wp.xz.cn/plugins/wordpress-social-login/
Please advise if you have more questions.
Best Regards,
WPMU DEV
