The goal of this study is to refine and test a psychosocial intervention called ASCENT (ACT-based Supportive intervention for patients with CENTral nervous system tumors). This intervention was developed to help patients after being diagnosed with a brain tumor. The main question this study aims to answer is whether this intervention is feasible (i.e., possible to carry out) and acceptable (i.e., considered helpful) to patients. Participants will be asked to take part in 6 coaching sessions and complete short surveys at four different time points. Some participants will be asked to share feedback via interviews.