I am trying to create a Business Process Flow and integrating either Workflow Step or Flow Step. However, I cannot complete the business process flow because I am unable to select any of my created Workflow or Flow. Please find the screenshots below:
Created and Activated a Workflow Process (using the New Workflow wizard):

It does not appear from the dropdown selection:

Also tried creating a Flow:

Also does not appear in the dropdown pane for Flow Step:

Am I missing something or doing something wrong?