How to Turn off Auto Sign-in in Edge Browser
Microsoft Edge is designed to be fast, safe, and easy to use. Since it is built on the Chromium engine, it works well with most websites and supports extensions from the Chrome Web Store.

Edge has useful features like Collections to save and organize webpages, vertical tabs for easy multitasking, and built-in tools such as a PDF reader and screenshot capture. It also offers privacy controls to block trackers and gets regular updates for better security. Because it connects well with Windows and Microsoft 365, Edge is a good choice for both work and everyday browsing.
It however automatically signs you in based on your sign in info from Outlook and other sites. If you would like to keep this turned off, then here is how to do it:
Open Edge browser and from the address bar, type in:
edge://settings/profiles

Scroll to the Profile settings section and click on Profile preferences.

Turn off the option that says Automatic sign in on Edge.

When this is off, you will be asked to login to Edge even if you have signed into other sites with your Microsoft account like Outlook.
Happy browsing.