You are in Milan and you need to come back to your Country for a few days.
You have just bought your flight ticket and the departure is just a couple of days.
Therefore you need to make the Covid test very soon, to get the result in time.
How to quickly do it in Milan?
I would suggest you to contact “Nuova Farmacia Beretta”  by phone ‎+39 02 5831 5686, or go there, their address ‎Via Bligny 47, Milan.
They are open from 8 am to 8:30 pm, from Mon to Sat and from 9 am to 8 pm, on Sunday.
You could book the test even for the same day. They have a “tent” on the street, at the crossing with Viale Sabotino, very close to Bocconi.
Once you are in the pharmacy, you should just fill a form and pay € 40 or € 95 for molecolare test.