check nodejs installation:

nodejs -v

check npm installation:

npm -v

sudo npm install -g npm@latest
sudo npm cache verify
npm -i
sudo npm install --no-optional
sudo npm init
sudo npm install -g @angular/cli

Unhandled rejection Error: EACCES: permission denied, open '/home/onizu/.npm/_cacache/tmp/b5bc4345'S: permission denie

sudo chown -R $USER:$GROUP ~/.npm 
sudo chown -R $USER:$GROUP ~/.config
sudo chown -R root:YOUR_USERNAME /usr/local/lib/node_modules/
sudo chmod -R 775 /usr/local/lib/node_modules/

install git (if not installed):

sudo apt-get install git
git config --global user.email "[email protected]"
git config --global user.name "your name"

create workspace & app:

ng new my-app

serve app:

cd my-app
ng serve --open

the app should be available at: http://localhost:4200/

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