Check the Microsoft Accessibility / Teams page at:
Freedom Scientific has done a Webinar Training on using Microsoft Teams. You can find the archeive at:
The last place I would recommend is Hartgen Consultancy. Brian has done a webinar that is available for purchase along with scripts that he has developed. There is a charge for the webinar recordings and scripts. You can find them Here:
There is amailing list of blind users using MS Teams and you can find it at groups.io by doing a search.