Fixing a joomla platform

Actually we have an issue with our joomla internet platform . The platform it is not more accessible on our siteground servcer. The reason might be the upgrade of the php version by the hosting provider. When we click on it nothing is displayed any more. It has to be fixe in other for the site to be accessible again through the weblink.
One of the solution can be to use lastest joomla version( which i assume is using php7 &php8) and reuse the database. In this case this will be basically a migration.