Clean start Database magento 2 / reinstall

You want to connect an existing magento 2 installation to a new database that is completely Clean.
one possible solution is this

Change this file: app/etc/env.php (in case you want to go back to the previous settings) -> for example, change it to app/etc/env.php--old.

Go to your magento webshop and the magento 2 setup wizard will restart. This is where you can specify your new database.