To request the assessment of curricular requirements and personal preliminary preparation for enrollment in a Master's Degree program without a predetermined number of available slots, you should follow the instructions provided in Section 3.3 of the Student Handbook for Tor Vergata University of Rome (page 14). Specifically, you need to access the Delphi Online Services website, select the Student Area, and then click on Button 1 for the request of curricular requirements assessment (page 14). Subsequently, you'll need to fill out the application for the admission test, and this will generate an application form along with a payment slip (page 19).