UI Flows are a preview capability launched this week at Microsoft Ignite. They're a robotic process automation capability that allows actions on desktop software or websites to be automated by Power Automate. In this video I go through the process of recording and automating a UI Flow using desktop software (Paint.Net) to add text to an image.
You can download the Chromium browser (Chrome, new Edge) plugin from here: https://chrome.google.com/webstore/detail/microsoft-flow-preview/jcajipieipkmjpfakbdhmjidmhidogoo
For the <Keys> commands used by Sendkeys, they appear to match what's listed here, e.g., <Keys.Enter>https://docs.microsoft.com/en-us/dotnet/api/system.windows.forms.keys?view=netframework-4.8