Hi @KarlS190
Add "Create user" action and pass the input variables by clicking on 'X' icon and select from the list:

In cloud flow, initialize a variable to store the value of an input parameter. I have taken DisplayName as an example. Set the value of it as per the logic.

Once you have the value in this variable, you could pass it to the desktop flow from the dynamic content window:

You could have used compose action to store the value of input parameter. In the same way, set the values of all input parameter in the cloud flow & pass it to the desktop flow to perform the required task.
If this helps & solves your problem, please remember to give a 👍 and accept my solution as it will help others in the future.
Thanks