How to trigger workflow from standard webdynpro application?

Hello Experts,

I am very new to workflow, I got a requirement to trigger workflow from standard webdynpro application.

Requirement is:

I need to create a button on the standard screen, by clicking the button i need a popup screen(custom). In the pop-up screen am using two fields and a button. On clicking that button, workflow needs to trigger (basically an email is sent to the higher authority/manager). The manager can either approve it or reject it. But i need to check the status and store the status in a Database Table basically a custom table.

Do we got any standard workflow to do this type of requirement or need to create a custom workflow for it??

Your Inputs are very much appreciated.

Thanks,

Mohsin