You can create a Meet via a Calendar event or ad-hoc (via https://meet.google.com/).
You may start a Meet with one person and then want to add others in later, whilst the Meet is in progress.
Here’s how you can quickly access the Meeting Details:
In a Meet:
Click on Meeting Details (bottom left). In the pop-up you will see the details. Use COPY JOINING INFO to copy the.
You can then use the details in an email or chat message to a colleague and invite them in.
You will more than likely need to allow the user access to the meeting (via a pop-up requesting access).