"Autopark" requires being between two vehicles. There is no version of autopark where you get out of the vehicle. Thats summon, which is basically in a straight line avoiding obstacles in the way if possible.
Page 104 on this tesla manual covers autopark, its a page and half of instructions:
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To Use Autopark When driving, follow these steps to allow Autopark to maneuver Model 3 into a parking space:
1. When driving slowly on a public road, monitor the touchscreen to determine when Autopark has detected a parking space. When Autopark detects a potential parking space, the touchscreen displays a parking icon. Autopark detects parallel parking locations when driving below 15 mph (24 km/h) and perpendicular parking locations when driving below 10 mph (16 km/h).
NOTE: The parking icon appears only if the vehicle's position and/or the circumstances of the surrounding area are such that Autopark can determine an appropriate driving path. If Autopark cannot determine an appropriate path (for example, when driving on a narrow street where moving into the parking space causes the front of the vehicle to extend into the adjacent lane), you can either reposition the vehicle, find a different parking space, or park manually.
2. Check to determine if the detected parking space is appropriate and safe. If so, pull forward and stop approximately a car length ahead of the parking space (as you normally would when parallel parking or when backing into a perpendicular parking space).
3. Release the steering wheel, shift Model 3 into Reverse, then touch Start Autopark on the touchscreen.
4. When parking is complete, Autopark displays the "Complete" message. In situations where Autopark cannot operate due to inadequate sensor data, the touchscreen displays a message indicating that you must manually park Model 3.
NOTE: If you press the brake when Autopark is actively parking Model 3, the parking process pauses until you touch Resume on the touchscreen. NOTE: Autopark detects potential perpendicular parking spaces that are at least 9.5 feet (2.9 meters) wide with a vehicle parked on each side. Autopark detects parallel parking spaces that are at least 20 feet (6 meters), but less than 30 feet (9 meters) long.
Autopark does not operate on angled parking spaces. WARNING: Never depend on Autopark to find a parking space that is legal, suitable, and safe. Autopark may not always detect objects in the parking space. Always perform visual checks to confirm that a parking space is appropriate and safe. WARNING: When Autopark is actively steering Model 3, the steering wheel moves in accordance with Autopark's adjustments.
Do not interfere with the movement of the steering wheel. Doing so cancels Autopark.
WARNING: During the parking sequence, continually check your surroundings. Be prepared to apply the brakes to avoid vehicles, pedestrians, or objects.
WARNING: When Autopark is active, monitor the touchscreen to ensure that you are aware of the instructions that Autopark is providing. To Pause Parking To pause Autopark, press the brake pedal once. Model 3 stops and remains stopped until you touch Resume on the touchscreen. To Cancel Parking Autopark cancels the parking sequence when you manually move the steering wheel, change gears, or touch Cancel on the touchscreen.
Autopark also cancels parking when:
• The parking sequence exceeds seven moves. Autopark 102 MODEL 3 OWNER'S MANUAL
• Model 3 detects that the driver is exiting the vehicle.
• A door is opened.
• You press the accelerator pedal.
• You press the brake pedal while Autopark is paused.
• An Automatic Emergency Braking event occurs (see Collision Avoidance Assist on page 113).
Limitations Autopark is particularly unlikely to operate as intended in these situations: • The road is sloped. Autopark is designed to operate on flat roads only. • Visibility is poor (due to heavy rain, snow, fog, etc.). • The curb is constructed of material other than stone, or the curb cannot be detected. • The target parking space is directly adjacent to a wall or pillar (for example, the last parking space of a row in an underground parking structure). • One or more of the ultrasonic sensors is damaged, dirty, or obstructed (such as by mud, ice, or snow). • Weather conditions (heavy rain, snow, fog, or extremely hot or cold temperatures) are interfering with sensor operation. • The sensors are affected by other electrical equipment or devices that generate ultrasonic waves.
