ThreatCop allows its users to send emails only to the verified domains. The users need to follow the steps given below to add and verify any domains.
Step 1: Go to the ThreatCop Dashboard. Click on the My Profile icon and select Settings.

Step 2: Go to the Domain tab.

Step 3: Enter the new domain you want to add in the Domain Name field and click on Add.

Step 4: A pop-up box will appear on your screen with a set of instructions. Copy the txt record available in this box and update it on your DNS. Once you have updated the record, click on Verify to complete the process.

Once you have added and verified a domain, you can send phishing emails to that particular domain.