Is it must npm install , I want yarn add ?

[dAskyacc]

error An unexpected error occurred: "https://registry.yarnpkg .com/vue-clipborad2: Not found".

[Inndy]

$ npm init
This utility will walk you through creating a package.json file.
It only covers the most common items, and tries to guess sensible defaults.

See `npm help json` for definitive documentation on these fields
and exactly what they do.

Use `npm install <pkg>` afterwards to install a package and
save it as a dependency in the package.json file.

Press ^C at any time to quit.
package name: (yarn-test)
version: (1.0.0)
description:
entry point: (index.js)
test command:
git repository:
keywords:
author:
license: (ISC)
About to write to /tmp/yarn-test/package.json:

{
  "name": "yarn-test",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC"
}


Is this OK? (yes)
$ yarn add vue-clipboard2
yarn add v1.16.0
info No lockfile found.
[1/4] Resolving packages...
[2/4] Fetching packages...
[3/4] Linking dependencies...
[4/4] Building fresh packages...
success Saved lockfile.
success Saved 6 new dependencies.
info Direct dependencies
└─ [email protected]
info All dependencies
├─ [email protected]
├─ [email protected]
├─ [email protected]
├─ [email protected]
├─ [email protected]
└─ [email protected]
Done in 0.41s.
$

It works with yarn. Check your yarn config.