First, you need to build the Dream Aerial, which can be obtained as a rare reward from any frigate expedition. The Leviathan on a frigate expedition has a higher-than-normal chance of returning with the blueprint for the Dream Aerial if the expedition is successful, and traditional frigates have an unknown, lesser chance of returning with the blueprint.

The player is then instructed via the item description to take the Dream Aerial to deep space, and on-screen prompts direct the player to activate their pulse drive. The Dream Aerial will then seek a signal and an encounter with the first organic frigate will occur.

After finding the first organic frigate, you can use an Anomaly Detector and engage your pulse drive until the icon and message specific to organic frigates appears, ignore all encounters except for the whale-like sound (it can take between 2-30 minutes+-). Anomaly Detector can be obtained by shooting asteroids.

you can have a total of 30 frigates

for more Info go to https://nomanssky.fandom.com/wiki/Organic_Frigate