Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello,
Do you mean, you want to use your business account as your Windows log in?
If so, first of all, you need to make sure your computer is running Windows Pro edition, If it is Home edition, then you won't be able to add a work account.
If you have Pro, to do so, go to Settings > Accounts > Access Work or School, click on Connect.
Don't sign into your work email yet. Instead, click on "Join this device to Microsoft Entra ID". On the next step, you will be prompted to sign in, then you can sign in.
Once done, restart the computer and you can use "switch user" to sign in using the business email.
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I do want to add that, if this is your personal device, or if your business only has a few devices, this is not recommended. Setitngs Windows log in with business accounts is ideal only for organization managed devices, so that IT team can managed all company devices from Microsoft Admin Center. If you just manage your own device directly or only a few device, that's an overkill and it will only over complicate managing your device.