The error should be self-understood. PHP lacks a way to connect to a database server. Therefore the database content cannot be restored and your site cannot work properly.
As you can see in the phpinfo output you attached, you have not enabled mysqli or mysqlnd in your PHP. Therefore PHP has no way to connect to a MySQL (or MariaDB, it's the same API) database server.
You need to enable MySQL database support in PHP before trying to restore the site. You can do so enabling either mysqli or mysqlnd support. Please ask your host for instructions on doing that. The exact steps to do that depend on how the server is set up, something you are paying your host to manage for you.
I'd also like to point out that you are planning on using PHP 7.0 on this site. I advise against it. PHP versions 5.6 and 7.0 will become end of life in December 2018, therefore they will no longer receive security updates and bug fixes. We very strongly recommend using PHP 7.2. You can read more about the lifecycle of PHP releases and the planned end-of-life dates at the official PHP site's Supported Versions page
Nicholas K. Dionysopoulos
Lead Developer and Director
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