A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
You cannot share some of these news with external users, you could share the entire communication site with external users to make news available.
After sharing the entire communication site with external users, they can sign in with personal outlook account, view the entire communication site, access to documents and make comments. They cannot add users.
Here're steps:
1.Go to MIcrosoft 365 admin center -> Users -> Guest users -> Add a guest user.

2.Enable external sharing in the tenant level. Go to SharePoint admin center -> Polices -> Sharing -> Set Anyone in the Content can be shared with section.

3.Enable external sharing in the tenant site level. Go to SharePoint admin center -> Sites -> Active sites -> Select the site -> Sharing -> Set Anyone in the External shaing.


4.Go to the communication site -> Site permissions -> Share the site -> Add the guest user account.
5.Guest users will receive an email invitation, click the URL in the email invitation, go to the communication site.

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.