Npm installed under ubuntu, failed?

  node.js, question

Before I installed sudo apt-get install node, it was always unsuccessful, and then I saw on sf that there was a folder for node in inside, ubuntu system, so it was not successful? I forgot what I said
Then i installed it in his way, sudo apt-get install nodejs.
When using node, use nodejs to command
Now the problem comes, I want to install typescript, but I need to install npm first, but I did not respond to the input of npm -v at the terminal, I guess it is the same reason that node was not successfully installed before.
How should I install it now?

Nvm is recommended for installation and is also convenient for version management.
Go to githubnvm