You may want to rethink your approach as money is your first priority.
To install W10 you need an installation copy of W10 plus a genuine Microsoft key to validate the OS. Living in Italy you will be able to cope with the language so visit the Italian eBay site to buy what you need. If you have the expertise you could just buy the key to download and use an ISO of W10 for the install. Some time ago now I used something called the Media Creation Tool available free from the Microsoft website to do just that. If you prefer buy an actual disk and key together that'll cost much more but will be straightforward and lots cheaper than a purchase from Microsoft.
Supposing that you buy a foreign language edition of Windows it's unlikely that you will be able to change it to English. Also be clear about the version of W10 you want and whether it is going to be 32bit or 64bit. A Windows key is tied to a particular version. For example, a key for W10 Home won't be any good with W10 Pro.
I've not given a direct answer to your question but if you want to purchase from Microsoft ask them yourself. That way, you'll know for certain.