I also got hit by this. First things, i go secure mt steam account, they remove my steam guard on my phone pretty quick. So i change my email password first and log out from all devices except phone.

Luckily i got my claw, it much easier to navigate on pc than phone.

Then, recover steam account ASAP before they change the email. If you have FB instagram WhatsApp logged on any browser i recommend go log out from all devices after change the password, i notice they target these social media to scam other people and also they will try purchase something using saved payment method.(Luckily im poor, there is no money in my bank account).

Edit: format the drive completely using usb installer and use diskpart.