We’ve reached the point in Microsoft’s series where it’s time to start
Upgrading Dynamics GP 2018 Web Client – Microsoft Dynamics GP Community
Upgrading Dynamics GP 2018 Web Client – Microsoft Dynamics GP Community
Install, Upgrade & AdminMicrosoft & the GP EcosystemGP 2018
Archived post from 2017. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.