Should I buy from the Italian market

Hi, I'm a huge newbie at this, I'm a student but I wanted to start putting away 20% of my allowance(20€) in SP500, mainly to get the habit of putting something away and not let just it die at the bank, however I've been buying the SP quoted in pounds, and only now I noticed the FX tax, I know that at this values it's basically irrelevant but should I sell what I have (40€) and put it the SP500 from the Italian market (I'm using the vanguard one) should I keep the 40€ where they are but forward buy from the Italian one, or should I just keep buying the same one, thanks for losing time on this probably stupid question