Enable cors for Chrome browser

I have a problem with enable cors. Browset blocked request despite I install and turn on addon Allow CORS: Access-Control-Allow-Origin form Chrome. I tried set different options but all the times request is blocked. Cors I tested here: https://webbrowsertools.com/test-cors/.
I make script with axios but effect is this same:

const onSubmit = data => {
      const headers = {
    'Access-Control-Allow-Origin': '*'
};
    axios.post('[url]', {
        'username': 'Hello123',
        'emailaddress': '[email protected]',
        'password': 'Test123@',
        'confirmpassword': 'Test123@'
    }, headers)
    .then(() => console.log('this works'))
};

What is wrong?