Using Classic Outlook on Windows for personal email, calendar, and contact management
Hi. I'm Brian and I'll try to help.
Who is your mail provider - that is, what follows the @ in your address? Have you tried adding your account back in by yourself? Which version of classic Outlook are you using?
The process if to click File>Add Account, enter your address and click Connect. You may be asked for your password, which you supply, then you click OK, then Finish. Outlook should configure your account automatically and you should have access to your mailbox. Here's Microsoft's guidance for the process: https://support.microsoft.com/outlook/getstarted/add-an-email-account-to-outlook-for-windows