Dear @fabiennne
Best wishes āØ
If your Web Host offers "One-click Wordpress install" or something similar this is recommended.
Do you still have access to your 'Malware' versioned website? You still have access to your Lay Theme content?
Please be sure that everything is backedup before proceeding:
https://laytheme.com/documentation.html#moving-website
Talk soon and have a wonderful day Fabienne š
Richard