All Staff chromebooks should automatically install the Remote Desktop app on their chromebooks at first log in. If not ensure the user and device are in the correct OU's on the Google Admin Console.
Click on the 3 lines in the top left and click user accounts, then add the users SIMS account details.
Open the remote desktop app, and click the + symbol in the top right corner, then click on add workspace.
In the URL type -
and for account select their account from the dropdown.
It should now appear under the workspaces on the homepage.
If there is an error message appearing when connecting to SIMS, then click the 3 dots next to the SIMS icon and remove the connection. Readd it using the above steps and it should connect after that.