Async functions run sequential, why? [duplicate]

I know that those methods area still synchronous, but that's not the topic. I'm currently going from synchronized nodejs-methods to async ones. I am just asking that if async methods return a promise, how is it that it runs before the end console.log statement.

I'm a bit confused about async functions. It says that they return a promise. A promise usually does not immediately run before the rest of the code, because javascript works with the "run to completion" approach.

But if async functions return a promise, how can you explain this?

const _prefixJS = async file => {
  console.log('running...')
  fs.copyFileSync(file, `${file}.bak`);
  const content = fs.readFileSync(file, 'utf8');
  // Some modifications...
  fs.writeFileSync(file, newContent);
  console.log('stopping!')
};

console.log('start')
_prefixJS(f);
console.log('end')

// Output: start > running... > stopping! > end

In my opinion, the output should be: start > end > starting... > stopping!

Because promises run concurrently and they are placed at the end of the event loop.