Step 1: Sign Up for a Free Developer Account
https://developer.avalara.com/freeTrial/

Click Start AvaTax Trial
Fill in your details and click Next. On the page Review your order click Start your Free Trial

Step 2: In your personal account, click on the icon with three stripes in the upper left corner.

Avalara License API key 1

In the window that appears, click Settings - License and API keys

Avalara License API key 2

On the License and API keys page, click Create License key

Avalara License API key 3

Enter any key name and click Сreate.

Step 3: After that, copy the License Key Code, copy Account ID and Company Code and paste them into the Avalara Tax module on your new website and Save
Avalara License API key 4