In zip file you will find a catalog with plugin:

Now you should copy it to the [your nopcommerce website directory]\Plugins

You can also upload it directly from the admin panel, just use the “Upload plugin or theme” button in the [Configuration/Plugins/Local Plugins].

After that, log in to your admin panel and go to [Configuration/Plugins/Local Plugins] and click [Reload list of plugins]

Please find [QuickProducts] on plugins list, and click Install.