The sump plug is located on the base of the engine, it is accessed underneath the car
You may need to remove the undertray
Undo the fixings - use a Torx-25 socket. Caution: the undertray is heavy and should be fully supported when removed
Don't forget to place a suitably sized receiving tray beneath
Using a 19mm spanner or socket, carefully remove the sump plug and fully drain the oil.
When the sump has emptied, wipe clean the sump plug area with a paper towel and refit a new sump plug and washer
Do not over tighten - replace the undertray