I'm afraid @EugeneL meant the updates for Meraki's hardware devices (switches, access points, firewalls, etc.), those are installed automatically. However your question was more about whether Meraki's MDM solution Systems Manager can deploy updates to the client devices it is managing right?
Afaik it can only do that for iOS devices, and only when they're DEP supervised.
See this:
Source:
https://documentation.meraki.com/SM/Device_Enrollment/Systems_Manager_Agent_and_MDM_Profile_Enrollme...
Also this page specifically about using that feature for iOS:
https://documentation.meraki.com/SM/Apps_and_Software/Deploying_OS_Updates_with_Systems_Manager
Slightly related you can require your devices to have a specific OS version for compliancy purposes, and use the compliancy status to do other stuff (like installing certain apps, provide access to corp wifi, etc.):