Step 1: Go to https://www.funcaptcha.com/, click on Get FunCaptcha button at the upper right conner of the screen. A popup window will be shown as shown below:

get-funcaptcha
Here you enter your email, your domain and select your plugin as WordPress. Once done, press “ Register” button. After that, you will be required to verify your password before get started

Step 2: Access on https://www.funcaptcha.com/domain-settings/ to get the FunCaptcha key as follows:

funcaptcha-key

If you have a more general question relating to the extension, you might consider visiting the question section and asking your question in https://www.designwall.com/question/.