Boost is designed so that teachers and students are able to use single sign-on with either their Google and/or Microsoft accounts. Once set up, users will automatically be signed in to Boost if they are signed in to Google or Microsoft.
Your schools Access Coordinator for Boost will have first have to authorise this in the Admin Hub. In the 'School tab' they can select which platform and accounts for which they wished to enable single sign-on:
Students single sign-on
For students to use single sign-on, their username for Boost must be an email address, and that email address must be the one they use for Google or Microsoft sign-in.
Teachers single sign-on
Teachers' email addresses for Boost can be different from their Google or Microsoft sign-in ones. If this is the case, teachers will need to log in to Boost first, then navigate to their My Account panel from within the Admin Hub and set up the link to Google or Microsoft themselves.