In the menu in the upper right corner you have an option called Page Designer that allows you to design the screens and e.g. hide fields.

You will of course need permission set rights to do so and I'd recommend that you get an understanding of how the context concept works before going to crazy. Your changes will affect everyone immediately if you don't. 

The  designer opens in the navigator.

That is great.

Is (Page Designer) function applicable for ESS Aurena configuration? some fields Employe Self-Service → personnel management are unwanted and should be removed/hidden.

I don’t see why not.  Just re-iterating that you should be careful and educate yourself on how it works before you make too many changes. The designs in Aurena are not linked to profiles but something called “contexts”.  You can find more information in F1 Technical Docs.

https://SERVER_URL:PORT/ifsdoc/f1doc/Foundation1/045_administration_aurena/220_Configuration/200_client_configurations/default.htm

The path is Foundation1 / Administration Aurena / Configuration Guide / Client Configurations 

Thanks for the caution and I will study well.

I will review and come back if there is any additional clarifications required. 

URL is not working for me!

You updated with your environment details? Which Update are you on? This may only be available for Upd5 and 6.