@Sanket1
Please follow the below steps:
Have you registered your machine with Power Automate Desktop yet? If not, please follow the steps below:
Manage machines - Power Automate | Microsoft Learn
If you have already completed the registration, then first verify whether your machine is showing as connected in the Power Automate cloud portal, as shown below.

Once the machine tab confirms that your machine is connected, proceed to add a desktop flow action in your cloud flow. Click on the three dots (...) in the action's top right corner and select "New connection." Fill in the required information.

In the machine/machine group dropdown list, select your registered and connected machine, and mention your username with the domain name(You can find this information by using the command prompt and typing "whoami" to get your username). Enter the same username with the domain in the connection panel along with your Windows password.
Finally you can pick your desktop flow and mode of run in the below window:

Hope this helps!!
Thanks,
Deenuji Loganathan 👩💻
Automation Evangelist 🤖
Follow me on LinkedIn 👥
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