Hi Stanley...
Exchange online have a stronge capacity of send emails
but if u still need actived this service, Microsoft has a complete library of this information.
and
https://learn.microsoft.com/en-us/connectors/acsemail/
unfortunately it's not as simple as a single command like 3-part services enable with exchange online.
if your team or you do not have the knowledge to activate the service, I recommend that you look for a partner, it is very easy...
I hope this help u.
Regards