Building a Company Intranet with a SharePoint Online Site Accessible To All Employees

Hi Everyone,

I'm hoping someone can quickly point me in the right direction on this because after a couple of hours of reading, I'm a bit lost.

Our requirement is as follows: 

• To build a company Intranet using a SharePoint Online Site.
• The site should be accessible to all employees in the organisation, and to nobody else.
• However, only a small subset of employees have a Microsoft account and we don't want to change that.

This seems like it's probably a fairly common requirement.

Can someone point me towards the best approach to achieving these requirements, please?

Thanks,

Jason