Create a onchange event microflow, which you connect to both First and LastName input textboxes
This microflow will change the FullName based on $Employee/FirstName + ‘ ‘ + $Employee/LastName
Note that when one or both are empty you want to make choices:
This can be catched using decisions or if..then..else statements
there is several solution here.
In my opinion the best approach would be to put the fullname text box in non editable. Then in the first name and last name text box, you can call a microflow on change event. In this microflow, you are changing the employee object, on the attribute full name, you put $employee/FirstName+’ ‘+$employee/LastName.
I would recommand you to check in this microflow to only change the object if $employee/FirstName and $employee/LastName are not empty