Yes, you can share your lecture/meeting. Simply copy the URL of your meeting and paste it into an email.
If the person outside of Neumann is going to be a presenter in your meeting/lecture- it highly recommended to be sure they have the actual Microsoft Teams App installed on their computer. The web version of the MS Teams App doesn’t offer all the features that actual App has. (For example- you can not share desktop audio in the web version of MS Teams)