Well you said "after you get a phone" that's why I asked, you need additional security methods to keep your account secure and be able to recover it later. you can use Microsoft Authenticator app on IOS and Android easily access your account password-less or use the code the app generates for secure login.
if you don't have that, you need to enter a phone number to receive SMS codes.
if you don't have any of them, Contact Microsoft support: https://support.microsoft.com/ they are the ones that can help you. this section of community is only about the tech community website itself.