Install plugins and manage add-ons
Installing the free Woocommerce CSV importer and it’s add-on’s is the same like any regular plugin. In you admin you can goto Plugins->Add New. If you are installing Woocommerce CSV importer, you can search for it in the plugin overview. If you are installing an add-on, upload the zip file you can download from your account page just like it is a regular plugin. The plugin will create a folder in the uploads directory. Make sure it has to right permissions.
In the CSV Import -> Add-ons page you can see a list of installed add-ons, there versions and if there are new versions available.
If there are new versions and you still have a valid license, you can download them from your account page.
For additional information an how to install plugins, look here.