When you create an announcement, if you make sure Notify employees is selected before you publish it, everyone in your Sage HR company will receive an email notification to view it.
After you've published an announcement, if you want to send any previous announcement to someone, you can copy a link for it and send it to them, whether by direct message, in an email etc.
On the main menu click Announcements.
On the relevant post, click on the three dots.
Click Copy link.
When someone clicks on that URL, as long as they have access to your company, they can log in and are taken directly to the post.