There are two points
When a document should be submitted
e.g. when document is in draft state it should be submitted to get approval. Or if a document need a change, after approval, it can go for resubmission.
This is done by overriding canSubmitToWorkflow() method on table level
When it should go under a certain Approval
This is taken into consideration when a certain approval step is optional. e.g. if your leave request has to be approved by your manager and there is condition that if leave days are more than 30, it should also go to Division Manager of company. In this case the second step of approval is conditional that is Division Manager will approve only in case, if you leave application days are more than 30.
From your provided screenshot, I can see you are attempting #2 scenario. What you want to do, I don’t know from your previous description, as provided details are not understandable (to me)
Kindly explain your issue in better way to get an appropriate answer