Securing Uninterrupted Pandemic Preparation Of Resources and Therapies Act or the SUPPORT Act This bill expressly incorporates the provision of mental health and substance use disorder services during public health emergencies into the authorities and other activities of the Substance Abuse and Mental Health Services Administration (SAMHSA). Additionally, SAMHSA must report to Congress about recommendations to improve the provision of such services during public health emergencies. The Government Accountability Office must also report on SAMHSA's programs and activities for supporting the provision of such services during the COVID-19 pandemic.