As of May 20th, 2023, the minimum version of Zoom required to join meetings is 5.11.4 on Windows, and 5.11.0 on MacOS. If you attempt to join a meeting and don’t have the minimum version, you’ll be prompted to update, or offered a link to join via the browser instead. If you don’t use a standalone Zoom app (Windows, MacOS, Android, iOS, etc.), but instead normally join meetings by clicking a link and joining in your browser, you don’t need to do anything.
The Zoom Software Quarterly Lifecycle Policy (instituted by Zoom in November of 2022) is intended to make sure all users are joining meetings with a minimum level of security and features. You can find more information on the Zoom Software Quarterly Lifecycle Policy, and the minimum versions for other devices and platforms, here.