When using nvm to download a higher version of node, npm is not automatically downloaded. I saw that there are many answers on the Internet that copy a copy of other versions of npm to upgrade,
but there will be strange errors,
so we use other methods
to set up npm images for nvm , you can automatically download npm
1. First delete the node version that you do not have npm
nvm uninstall 16.0.0
2. Set up npm mirror
nvm npm_mirror https://npm.taobao.org/mirrors/npm/
3. Re-download the specified version
nvm install 16.0.0
4. Check if npm exists, success
