anjanesh if you don't want the overhead of nvm then you can just download a binary release of nodejs, eg:
mkdir -p ~/opt/src
cd ~/opt/src
wget https://nodejs.org/download/release/v14.17.0/node-v14.17.0-linux-x64.tar.xz
cd ~/opt
tar xf src/node-v14.17.0-linux-x64.tar.xz --strip 1
When that's done, the newer node and npm will be installed at ~/opt/bin/
To use it interactively first run:
export PATH=$HOME/opt/bin:$PATH
To use it in your apps, edit your app's start script to run /home/username/opt/bin/node
instead of the system node.