npm and node commands not found

I am trying to install Node.js

Originally I tried to install it using apt-get install ....

However I later realised that these were out of date and uninstalled them using:

$ sudo apt-get --purge remove node
$ sudo apt-get --purge remove nodejs

I then followed the instructions here:

https://nodejs.org/en/download/package-manager/#debian-and-ubuntu-based-linux-distributions

which basically says to do the following:

curl -sL https://deb.nodesource.com/setup_6.x | sudo -E bash -
sudo apt-get install -y nodejs

I did this and it seemed to install fine! However the issue I have is the commands npm and node is not recognised! However the command nodejs is recognised.

I checked the directories /usr/local/bin and /usr/bin, but could not find node or npm. I did find nodejs though.

How do I fix this issue?

via Yahya Uddin