Before deploying Trellix FRP without Self-Protection, you need to ensure that the 'Disable Self-Protection' checkbox is selected in the Product settings.
To install Trellix FRP without the Self-Protection feature enabled, you need to ensure that the keyword NOSELFPROTECTION is included in the command line parameters for the Trellix FRP deployment task in ePO - On-prem. This step disables the Self-Protection feature until the first policy enforcement, and ensures that the Self-Protection component is not installed on the system.
For more information on installation steps, see Deploy the software to managed systems.