See Tesla Model Y Owner's Manual, Page 159:
https://www.tesla.com/sites/default/files/model_y_owners_manual_north_america_en.pdf
The button on the charging connector opens the charging port. To unlock the charging port to remove the charging connector press and hold the button. (The light on the charging port will change from green or blue to white when the charging port is open and unlocked.)
You can start and stop charging from the Charging screen in the Tesla vehicle or from the Tesla app. Once you have stopped charging you can unlock the charging port and remove the charging connector from the charging port.
For daily charging do not charge beyond 90% state of charge (SOC).
Tap the number to the left of the battery icon to switch between estimated range and % SOC. (Else, the battery indicator can be set to display % SOC or estimated range within the Display Settings.)
Charge Port Light
WHITE: The charge port door is open. Model Y is
ready to charge and the connector is not inserted, or
the charge port latch is unlocked and the connector
is ready to be removed.
BLUE: Model Y detects that a connector has been
plugged in.
BLINKING BLUE: Model Y is communicating with the
connector. Either Model Y is preparing to charge, or a
charging session is scheduled to begin at a specified future time.
BLINKING GREEN: Charging is in progress. As Model Y approaches a full charge, the frequency of the
blinking slows.
SOLID GREEN: Charging is complete.
SOLID AMBER: The connector is not fully plugged in.
Realign the connector to the charge port and insert
fully.
BLINKING AMBER: Model Y is charging at a reduced
current (AC charging only).
RED: A fault is detected and charging has stopped.
Check the touchscreen for a fault message