npx command not found: create-app code example

Example 1: command not found:create-react-app

npm install -g create-react-app
...then start creating react app
npx create-react-app my-app

Example 2: command not found: create-react-app

Open Terminal
Go to c:/users and run dir /x 
check shorter name of your usernsme you found with dir/x 
//In my case my username is Nandini Jain and I got short id= NANDIN~1
and run npm config set cache "C:/Users/<shortname-you-found-with-dir/x>/AppData/Roaming/npm-cache" --global
//I ran the command
//C:/Users/NANDIN~1/AppData/Roaming/npm-cache" --global
  now run
  npx create-react-app my-app

//HOPE THIS WILL WORK BECAUSE ITS THE ONLY REASON OF YOUR QUERY.