Microsoft’s xCloud, the cloud game streaming component of Xbox Game Pass Ultimate that doesn’t require a console to use, is rolling out fully to iOS devices, including iPhones and iPads, as well as PCs and macOS computers via the web.
Of course you can. As long as you run an up-to-date browser, you can stream xCloud. Safari is supported but in my experience, Chromium-based browsers run it better (i.e. Chrome, Edge, Brave etc.).