install nodejs and npm in ubuntuy code example
Example 1: ubuntu 18 install nodejs
cd ~
curl -sL https://deb.nodesource.com/setup_12.x -o nodesource_setup.sh
sudo bash nodesource_setup.sh
sudo apt install nodejs
nodejs -v # shows your version
Example 2: install node js using nvm ubuntu
curl -sL https://raw.githubusercontent.com/creationix/nvm/v0.33.11/install.sh -o install_nvm.sh