Prerequisites

Provision of the VM instances on GCP as per Forcepoint supported hardware requirements available in the System requirements.
Configure the networking as per need and open relevant ports, including RDP port, listed in the Forcepoint DLP ports document for both inbound/outbound communication in GCP Firewall.
Forcepoint DLP requires a static IP, so allocate a private static IP for the Forcepoint Security Manager, SQL server and Supplemental server.
Install MS SQL Server, use the supported SQL to host Forcepoint Security Manager data as listed in the Certified Product Matrix for supported versions and run the scripts provided by Forcepoint support to configure it for FSM installation.
Enable an External IP for the instance. It is mandatory for the server, which will contain the Endpoint Server (main FSM or Supplemental Server, or both). Note that for functioning of FSM system, the External IP address should be reserved as static one.