Auto park is a feature of FSD. To see what the difference in the feature set is, you can refer to Teslas website on it:
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Autopilot is an advanced driver assistance system that enhances safety and convenience behind the wheel. When used properly, Autopilot reduces your overall workload as a driver. Learn more about Autopilot.
www.tesla.com
Autopilot
Autopilot includes the following functionality and features:
- Traffic-Aware Cruise Control: Matches the speed of your vehicle to that of the surrounding traffic
- Autosteer: Assists in steering within a clearly marked lane, and uses traffic-aware cruise control
Full Self-Driving Capability
Your vehicle will be able to drive itself almost anywhere with minimal driver intervention and will continuously improve. In addition to the functionality and features of Autopilot, Full Self-Driving capability also includes:
- Navigate on Autopilot: Actively guides your vehicle from a highway’s on-ramp to off-ramp, including suggesting lane changes, navigating interchanges, automatically engaging the turn signal and taking the correct exit.
- Auto Lane Change: Assists in moving to an adjacent lane on the highway when Autosteer is engaged.
- Autopark: Helps automatically parallel or perpendicular park your vehicle, with a single touch.
- Summon: Moves your vehicle in and out of a tight space using the mobile app or key.
- Smart Summon: Your vehicle will navigate more complex environments and parking spaces, maneuvering around objects as necessary to come find you in a parking lot.
- Autosteer on City Streets
- Traffic and Stop Sign Control: Identifies stop signs and traffic lights and automatically slows your vehicle to a stop on approach, with your active supervision
The currently enabled Autopilot and Full Self-Driving features require active driver supervision and do not make the vehicle autonomous. Full autonomy will be dependent on achieving reliability far in excess of human drivers as demonstrated by billions of miles of experience, as well as regulatory approval, which may take longer in some jurisdictions. As Tesla’s Autopilot and Full Self-Driving capabilities evolve, your vehicle will be continuously upgraded through over-the-air software updates.
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As shown in the list of features, the only thing with autopilot (which is presumably what you had before you got the FSD update, but you didnt say what year your model 3 is) is traffic aware cruise control and autosteer. Everything else, including auto park, is a feature of FSD (or enhanced autopilot if that is available to you).