Microsoft Account Setup for Small Business

M365/IT administrator who can handle account cleanup, Sharepoint setup and hands-on Windows troubleshooting:

This is for a small nonprofit business. We started with one employee with one laptop.
We are now two employees, each with a business-owned laptop, and three managing officers without company laptops who just need access to accounts and files in the case the employee vanish or need to be replaced.
We have business emails set up in Microsoft. The Microsoft 365 admin center and accounts have been cobble together haphazardly as we grew and added users. We need someone to advise how the Microsoft accounts should be set up - which MS pieces we need (don't even know what Azure or InTune are...?)
We have MS 365 Business Basic and MS 365 Business Premium. Ideally, we need 1) a cloud or sharepoint space to share all company documents; 2) the two employees and three officers set up to be able to access all documents and accounts as admins; 3) the employee's laptops set up correctly with the needed software.
The two laptops were purchased and set up this year, but are not working correctly. I'd like to see all documents stored off laptops and into the shared space, then clean/reload/re-set the laptops.
Laptop 1: Lenovo IdeaPad Windows 11 Home with MS Office Standard
Laptop 2: Lenovo Yoga Windows 11 Home with MS Office Home & Business 2024
This is a fairly simple job. We would like this completed ASAP as we cannot work until these items are fixed. Thank you.