When using 'npm' it requires me to login to github
to have such a problem, it means your command is wrong. take for example you are trying to install angular cli and you omit the @ symbol login will pop like so
npm install -g angular/cli // this will trigger login pop-up
npm install -g @angular/cli // will work fine
so check your command
我应该用cnpm install -g @vue/cli， 而不是cnpm install -g vue/cli， 少了一个@符号。