The relationship between Ph.D. and M.S. students and their advisors is critical throughout the entirety of a graduate program. Below are some resources from Cornell and elsewhere to help you with navigating this dynamic at all stages of your graduate career.
Advising Guide for Graduate Students
https://gradschool.cornell.edu/academic-progress/advising-guide-for-research-students-2020/
Advising Guide for Advisors
https://gradschool.cornell.edu/academic-progress/faculty-guide-to-advising-research-degree-students/