There is no reason you shouldn't be able to with a Surface Tablet as long as you are using a supported web browser. Internet Explorer is NOT a support browser so if you are using it that could be an issue. I suggest using either Google Chrome or Mozilla Firefox as your web browser.
To add with Rick's reply. Can you better describe what "can't get onto" means? Can you not get to the login page? Can you not log in? Or when you login, are you having issues? Thanks!