If you’ve downloaded the plugin, you can install them by going to your site’s dashboard, then go to ‘Add New’ under the Plugin menu item.
On this page there’s the main heading (‘Install Plugins’); below that there are some menu items; you want ‘Upload’
From there, click the ‘choose file’ button and select the zip file of the plugin you want to upload (fun tip: you can actually just drag and drop that zip file onto the field next to the ‘choose file’ button)
On another note, you don’t actually have to download the plugins if you’re getting them from somewhere on wordpress.org. You can install them straight from your Dashboard.
To do that, instead of going to the ‘Upload’ plugin area, head to ‘Search’ instead. Run a search and install the plugin you want. Once you’ve installed your plugin, go to the ‘Installed Plugins’ page under the ‘Plugins’ menu item. All your installed plugins can be found here and you can activate/deactivate/delete them here.
Hope that helps!
