Field Configuration: For using “Captcha” field, go to User Meta >> Fields Editor. Click “Captcha” field right sidebar. Then you can see the field configuration panel like in below. You can configure your field by using this configuration panel (show in below img-01).
Captcha Setting: Fill up the reCHAPCHA public key and reCHAPCHA private key for active the Captcha in frontend (show in below img-02) : Go User Meta >> Setting (in below you can find the reCHAPCHA setting).
Generated field: After complete the field confirmation and Captcha setting it will generated one field in frontend (show is below img-03)