@DigitsByAzure

If you are using the Virtual Terminal on a Web Browser, at this time, you will not be able to Add Services to this for check out, as Services are based in the Appointments App. 

You can check out the value through the Virtual Terminal, and mark the Appointment as paid in the Appointments App, but we're not able to import those Services into Virtual Terminal at this point. That would be immensely helpful though, and I am happy to surface this request with our Appointments team.