npx @capacitor/cli plugin:generate command displaying error ?

[TechRova]

I am trying to create a new plugin in capaciter for all of this

A plugin for Android , iOS , Web & PWA (all 4) to do this ::

1. Grant file storage access
2. Choose only Video File via file browser (single and multi)
3. Display Video in Video Player
4. Upload File as binary upload to Backblaze endpoint

So I tried to create a plugin with following command

mkdir myplugin && cd myplugin

npx @capacitor/cli plugin:generate

Now the npx @capacitor/cli plugin:generate command displaying error

Cannot open assembly 'plugin:generate': No such file or directory.

Why this error occuring ? pls help me?