Hi Vyom Goyal,
Thank you for reaching out to us on the Microsoft Q&A forum.
It appears that the platform you're trying to sign into requires a work or school email address, as personal email addresses (such as Gmail, Hotmail, etc.) are not supported for registration.
Here are a few options you can consider:
Use a work or school email address: If you have access to a work or school email account, you can use that to sign in.
Sign up for a Microsoft 365 account: If you don't have a work or school email, you can sign up for a free Microsoft 365 trial here. This will provide you with an organizational email address that you can use for signing in.
If you are still facing any issue, please let us know in the comments and where you are encountering this error along with the screenshot for reference. We are glad to help you.
If you found the information helpful, we would greatly appreciate it if you could acknowledge it by selecting the Accept Answer & Upvote options.
Thank you.