Do it by

1. Sign-in yourself in https://myaccount.microsoft.com/
2. Click the “My sign-ins” in the left-edge menu
3. Your recent active sign-in history is displayed

For detail, also refers to Microsoft’s newest document. (eg. search keywords “Microsoft365 recent activity” and read the Microsoft Support in that page.)
If you also want to change your password, please read this QA, ignoring the URL told in that document.

Do it by

1. Sign-in yourself in https://myaccount.microsoft.com/
2. Click the “My sign-ins” in the left-edge menu
3. Your recent active sign-in history is displayed

For detail, also refers to Microsoft’s newest document. (eg. search keywords “Microsoft365 recent activity” and read the Microsoft Support in that page.)
If you also want to change your password, please read this QA, ignoring the URL told in that document.