Complete hair loss on the scalp (which may be alopecia totalis) requires a professional diagnosis, as treatment depends entirely on the cause. If it is autoimmune-related, prescription therapies like JAK inhibitors (e.g., baricitinib) or corticosteroids can help. For advanced male pattern baldness, over-the-counter products like minoxidil are generally ineffective once all hair is gone; instead, hair transplants or cosmetic options are more viable. Please consult a dermatologist immediately. They will examine your scalp, identify the exact cause, and prescribe targeted medical treatments, which are much more effective than self-treating.