Language setting for Specific WordPress Page

My website is in English Language and using WordPress.

Html Code contains lang=”en-US” only.

But I want some of the page in other language like Spanish, Arabic and German.

When I create new page it is by default lang=”en-US”.

How can I set this lang=”es” or specific language attribute?

I have tried many plugins but all are converting every pages to selected languages that I don’t want.