You do not need to set the baseline in OpsCompass - your current state is set as the current baseline.
OpsCompass tracks the baselines for you, and shows the difference from your previous known state of each resource in the drift section with managed concerns.
You can see a complete history of each resource in the inventory.
Drifts can however, be acknowledged in OpsCompass by a member of the appropriate team, and moves them to an "acknowledged state". This allows users to track if they had eyes on drift, and document why drift took place.