Hello Bashar,
Welcome to Microsoft Community.
After reading the entire thread you posted here, I noticed that you actually posted two questions here. I can answer them individually, but be prepared that the end result may not be what you want.
1. How can we have one business account
Business account is a type of organizational account, usually assigned by corporate management, that has a dedicated domain name, which is used primarily to distinguish between accounts belonging to the company and external accounts.
So in theory, there is no way for an individual user to access a business account unless you are an employee of the company yourself. But when you first sign up for a Microsoft business product like Microsoft 365 for business, you will get an email address that ends with .onmicrosoft.com:
What's the difference between a Microsoft account and a work or school account? - Microsoft Support
- Visit Compare Office 365 Enterprise Pricing and Plans | Microsoft 365 to learn about and decide to try or buy one of Office365's product plans.
- Select the product plan you want to try or purchase, click "Buy Now" or "Free trial", select the service operation mode you want, and enter the Office365 organization account registration interface.
- After registration, you can directly log in to https://portal.office.com****with this account.
But this behavior is meaningless, an IT administrator in an enterprise can indeed see the health of all the devices in the entire company, but they are connected to the Surface Support for Business, if the device needs to be repaired, this will go into a completely different support channel than personal devices:
Contact Surface Support for Business and Education customers - Surface | Microsoft Learn
2. I have 2 surface pro 5 laptops that need to be sent in for service, they are stuck at the start up screen
If both of your Surface Pro 5's are in a non-starter state at this point and you'd like to have them repaired, I can usually direct you to the Surface technical support team, but unfortunately, because this model has been discontinued, out of warranty support and service for such models is no longer available. We appreciate your commitment to Surface and apologize for any inconvenience.
We'd love to help you upgrade to a new, more capable device. Please check out our online Microsoft Store, visit one of our locations in person, or chat with an expert to learn about ongoing and special promotions.
Best Regards,
Mitchell | Microsoft Community Support Specialist