Hi my name is ***** ***** to Just Answer. I am reviewing your question and will reply ASAP
Which aspect of the iPhone is blocked? Can you log in with your Apple ID on your computer?
Try logging in here: appleid.apple.com from your computer.
If it's your passcode there are different ways you can try to erase it and set it up again.
Let me know what error message it is and I can work out what kind of way it is blocked.
Here is the information on using iCloud to erase the device:
It requires Find iPhone active on the iPhone, but makes erasing it in any future case much easier.
You would need this to erase without Find iPhone enabled:
Hi Laurent, I will call you back, but first try to complete the iTunes install and launch, then type your reply here when you are ready. Thanks, David.
I'm thinking if this bit doesn't work, a remote desktop session would be better, I will do that with you if you can't launch iTunes this time, just let me know and I'll give the Chrome remote desktop link.
I'm trying to phone you back but it's failing for some reason, maybe the phone is in use.
I'm here for 5 more hours so feel free to reply here anytime and we will use Chrome Remote Desktop.
Please open Chrome web browser.
Click this link:https://chrome.google.com/webstore/detail/chrome-remote-desktop/gbchcmhmhahfdphkhkmpfmihenigjmpp
If it says Get App in blue on the top right, click it and follow the instructions.
Let me know when you can launch the App.
When you launch it click Get Started, then click the green Share button. Install any extra host software. Then when you see the 12 digit code reply here with it so I can remotely connect.
I can see this hurdle is causing a lot of time wasted, when you are more concerned about fixing the phone than this problem on the computer preventing that.
So I suggest another route, to connect to another computer that may already have iTunes installed.
I propose this as a faster way to get the main reason for contacting me in the first place which is the phone to be fixed.
If you can connect to another computer that has iTunes or can install iTunes, easier than fixing this computers problems, then it's just a matter of Restoring to Factory settings, and setting it up as new.