There are several Performance Rights Organizations (PROs) that provide licensing for live performance+synchronous live stream. Licensing payments fund artist royalties. These groups offer blanket licenses, renewable on an annual basis, that cover the use of their entire catalogs or licensing of individual works.
The University of Iowa has blanket licenses (or "small rights") for live performance of non-theatrical works with ASCAP, BMI, and SESAC. Any performance with theatrical elements, such as acting, sets, and choreography requires grand rights and must be licensed on a work-by-work basis.
If a performance will be pre-recorded and streamed at a specific date and time or distributed on the UI School of Music YouTube channel, it is NOT a live stream but a recording. Please consult the page on Licensing Recordings for more information.