The sump plug is accessed underneath the car. You will need to remove the undertray
Undo the fixings - use a 10mm socket for this - there are three plastic plugs to remove. Carefully remove the undertray. Caution - it is heavy and must be fully supported during removal
Don't forget to place a suitably sized receiving tray beneath
Using a 14mm 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