How to propose guest frontend translation for non-english people ?

[webafrancois]

I appreciate the translation work done for users, because for many non-IT people, English is still difficult to understand.
On the other hand, for the guest interface, the welcome language is always English.
Is it possible to offer different languages on the home page?
And if the browser language could be recognised, would that be wonderful?

Thanks a lot for your work!