Website WP dashboard DOWN

Hello,

I have the most important professional meeting of my whole life TUESDAY, and my website is DOWN. I can’t even log-in to my WP dashboard.

I was doing a backup yesterday that I have interrupted myself (for any reason), and since then…. NOTHING WORKS. I AM NOT A PROFESSIONAL AT ALL and I am French, I don’t understand nothing to all this and to difficult processes, I was just used to update/backup everything through my WP admin and since I can’t log-in anymore I am totally blocked.

My website is : https://www.EmmanuelleChoussy.com

Error message on my main page :
Votre serveur utilise la version 4.4.9 de PHP mais WordPress 4.1.1 nécessite au moins la version 5.2.4.
(In English it’s “YOU HAVE TO INSTALL THE LATEST VERSION OF PHP”)

When I try to log-in :
Parse error: syntax error, unexpected T_OBJECT_OPERATOR in /home/emmanuell/www/wp-admin/edit.php on line 169

I don’t know HOW to fix that without any access to my WP admin ! I need my website for Tuesday, it’s a true nightmare.

What I already did :

1- I uploaded the WP latest version and transfered the WP-ADMIN + WP-INCLUDES files through my FTP = didn’t change anything
2- Re-nammed the .htaccess files (I saw 2) in .htaccess_old = didn’t change anything
3- Email my HOST (OVH) and since it’s in France I will probably have a super fast reply next week….

I have a question :
each time I try to transfer files from my website LOCAL version to the ONLINE version, the files don’t show up at the same place. On my ONLINE version I have an INDEX file + a WWW file, and the transfered/new files show up at the ROOT, not in one of those files.

To be clear, my online version is like this :

www
Index.php
wp-includes
…etc….

> When I open www, I see :

wp-includes (another one but OLDER)
wp-content
wp-admin
…etc…

I don’t think it’s normal, but it was working like this before I did this backup yesterday.

Right now, I REALLY NEED TO LOG TO MY WP ADMIN…. please help ! Many thanks for your patience.