No, i have no withheld tax it's the tax charge that i get ontop of my sales which is 20% so i'm guessing it's VAT and it's only for sales in the UK but as a tax payer i dont have to pay VAT as i'm under the 80k threshold
No, it's not. William is right, Itch.io also withholds the taxes owed to the US government for running an online store out of there. And again, you don't pay the VAT in EU countries, the buyer does. It doesn't matter where you are based, in either case.