Yes, you need a Microsoft account to sign in to our services. If you don’t want to connect your email address with a Microsoft account, you can easily create an Outlook address for example and use that.
You already have a Microsoft account if you use an email address to sign in to Microsoft services such as Office 365 and Windows 10 PCs. You can also use email addresses from Outlook, Hotmail, Gmail, Yahoo, or other email service providers for your Microsoft account.