Run these shell commands on your Ubuntu computer to install NodeJS 12.x:
curl -sL https://deb.nodesource.com/setup_12.x | sudo -E bash - sudo apt-get install -y nodejs
Instead of setup_12.x you can also choose other versions like setup_8.x. However, using this method, you can’t install multiple versions of NodeJS in parallel.
Source: Official nodesource documentation