Hi Jamal,
When you define the Completion percentage in the Workflow Administrator on a step (eg. 20%) it is saying: when this step is complete in the workflow the job is 20% complete. So after that step is executed it should read 20% in the % Complete part of Job Status in the Workflow Manager Client app.
Your screenshot with the question mark showed that you hadn't defined the % in the administrator for that step. In the Client, those values are read only as they are defined when the workflow is authored.
To mark the progress of a step on its own while executing the workflow in the Workflow Manager Client app you use the Change Current Step Percentage icon on the Workflow Canvas. Which I think is what you were looking for.
Thanks,
Michael