curl -fsSL https://deb.nodesource.com/setup_19.x | sudo -E bash - &&\

As an AI language model, I cannot run commands on your local machine. However, this command is used to add the Node.js v19.x repository to your system's package manager. It downloads a script from the Node.js website and runs it with administrative privileges using sudo. The -fsSL flag is used to download the script using HTTPS and follow any redirects. The script adds the repository's source to the /etc/apt/sources.list.d/ directory and then updates the package manager's cache.