Change Lang tag without changing backend language

Hi!

I'm not sure if this is a native Wordpress or a generatepress thing.

By default we noticed the lang tag is set to English/USA:

lang="en-US"

I'm aware if you change the language in settings to our target language, it will change this tag.

However, this also also changes the backend language of Wordpress. For example, if I changed the languages settings to Spanish, it will change the lang tag, however the entire backed/wp-admin area will be in Spanish.

Is their a way to keep the admin area in English and change the 'lang' tag to our language of choice? ie an easy php function or something.

Thanks for your help!