Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Dear Gary Murphy2,
Good day!
Thank you for posting to Microsoft Community. We are happy to assist you.
As per the description you have shared, we understand that you want to add email encryption to your Microsoft 365 business standard subscription.
Basically, to enable or add e-mail encryption in your tenant, you need to have Micrsoft 365 Enterprise subscription (such as Microsoft 365 E3/E5 & Office 365 E3/E5). However, to access Microsoft basic message encryption, you must add Azure Information Protection Plan 1 to your Microsoft 365 Business Standard subscription. You can refer to the screenshot below and Exchange Online service description - Service Descriptions | Microsoft Learn
For additional information, you can refer to Set up Microsoft Purview Message Encryption - Microsoft Purview (compliance) | Microsoft Learn
We look forward to you update. Please feel free to let me know if there are any questions or if we've got you wrong. We will keep assisting you based on the information you provide. We sincerely appreciate your patience and cooperation.
Stay safe and healthy.
Have a good day!
Sincerely,
Libeamlak | Microsoft Community Moderator