There is no direct link to immediately hop on a video call, not yet at least :)
Workarounds would be:
1. Open your testroom which you'll find at the top right of your account. We use it for media checks before a meeting starts and/or internal meetings by just sharing the url with team members who then join instantly.
2. Schedule a call with yourself - using another email - and then share the meeting link with your guest.
3. Activate your Live Now feature to let people book you for calls immediately.