SHELL

install vue cli

npm install -g @vue/cli                           
//to see the version installed
vue --version

npm install cli vue

npm install -g @vue/cli
# OR
yarn global add @vue/cli

How to install vue cli

# npm
npm install -g @vue/cli

# yarn
yarn global add @vue/cli

npm install --global vue-cli

npm install --global vue-cli is now
npm install -g @vue/cli

install vue cli 3

installing vue cli commands
npm install --global vue-cli is now
npm install -g @vue/cli

vue cli npm commands

Globally install vue cli:
npm install -g @vue/cli

to check if vue cli is installed:
vue --version

to create vue project, go to your project directory & then:
vue ui
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Update:
npm update -g @vue/cli

install vue-cli

npm install -g vue-cli    //make sure you have node and npm installed 
vue init webpack <appname>  //  eg:  vue init webpack myapp
cd <appname>               // cd myapp
npm install
npm run dev  //server will start in port 8080