How do I allow SMS notifications so students can select this option from their profile and add the

We currently allow students to set-up email notification in Brightspace, we would like to give them the option to receive SMS notifications too. I found this article but it doesn't tell me how to turn on SMS notifications.  https://community.brightspace.com/s/article/All-About-Notifications?t=1651220803027 We already have 'notifications' selected but this only shows the email option. We also need to add our message provider details (we are looking at using a provider we already use to send other messages in house). I can't find any other articles on how to set this up.