Before you begin, make sure that you have installed & activated Elementor Plugin on your website.
Go to your WordPress Dashboard and navigate to Plugins -> Add New. Then in the search box search for ‘Unlimited Elements’. Then simply click on the ‘Install Now’ button.
After the installation is completed, click on the ‘Activate’ button and ‘Unlimited Elements for Elementor’ will be activated.
After the plugin is activated you have an option to opt in to get updates or you can skip this stetp.
Now you can view the widget library and install any widget you want by hovering over it with your mouse cursor and clicking install.