The primary aim of the study is to investigate the feasibility of a prehabilitation program, which consists of a set of strategies including physical activity, nutritional support, and psychological counseling, carried out before and during cancer treatment for patients affected by head and neck tumors. About 4 weeks before surgery or the start of curative chemo-radiotherapy, the patient will begin the prehabilitation program, which will continue in parallel throughout the duration of the treatment and for up to 2 weeks after its completion. This prehabilitation program will include a combination of physical activity exercises, nutritional counseling, and psychological counseling sessions, all of which will be individualized for each patient. At the time of tumor diagnosis (T0), after 4 weeks of prehabilitation and before the start of the planned treatment (T1), 2 weeks after the end of treatment (T2), and after 6 months (T3), the patient will undergo a medical visit to collect anthropometric data, vital signs, a 6-minute walk test, and will complete a series of questionnaires aimed at assessing the risk of malnutrition, the development of anxiety and depression, and questionnaires to evaluate their quality of life. Throughout the duration of the study (i.e., up to T3, 6 months after the end of cancer treatment), the patient will wear an electronic watch, provided by the study, designed to measure vital signs, the number of daily steps, and the type and minutes of physical activity.