To install the plugin, you can go to Plugin>Add New, search for WooCommerce and Install it. Alternatively, you can download it from here.
When you activate the plugin, you may be asked for the permission to install WooCommerce default pages. We recommend that you go through with this so that all the pages are created correctly.
After WooCommerce is activated successfully, you can use all its features, including widgets and shortcodes.
For further guide, please check WooCommerce’s official documentation.