How do I reset the motor oil indicator, back to 100% after having changed it?

That would be the easiest thing to do; however, my manual has been rather 'cosmetic' in providing information - indicating for instance that 'the motor oil should be changed regularly' and all the like... Otherwise, I would not have had bothered you, Pals ! Anyway, I will try to keep those 10 precious seconds at the earliest convenience !!! Thanks ! L.

Did you get it reset?

Thanks for your advice ! As a matter of fact the case with my car was a bit more complicated - for I have an electronic key: usually, the START/STOP button combined with the clutch pedal pressed down makes the engine start. However, in order to reset the engine oil indicator one has to switch the dashbord lights on - WITHOUT STARTING the engine! And THIS IS THE TRICK: in order to lit the diagrams on the dashboard one has to PRESS THE BRAKE PEDAL plus push the START/STOP button !!! After roughly ten seconds the lights go on [without starting the engine!] and then the reset/clear procedure may be successfully followed ... Once again - thanks to all of you for your kind attention, and advice. L.

Sorry didn't say Manuel and assumed it was an automatic.