This phase III trial uses the Decipher risk score to guide intensification (for higher Decipher gene risk) or de-intensification (for low Decipher gene risk) of treatment to better match therapies to an individual patient's cancer aggressiveness. The Decipher risk score evaluates a prostate cancer tumor for its potential for spreading. In patients with low risk scores, this trial compares radiation therapy alone to the usual treatment of radiation therapy and hormone therapy (androgen deprivation therapy). Radiation therapy uses high energy x-rays or particles to kill tumor cells and shrink tumors. Androgen deprivation therapy blocks the production or interferes with the action of male sex hormones such as testosterone, which plays a role in prostate cancer development. Giving radiation treatment alone may be the same as the usual approach in controlling the cancer and preventing it from spreading, while avoiding the side effects associated with hormonal therapy. In patients with higher Decipher gene risk, this trial compares the addition of darolutamide to usual treatment radiation therapy and hormone therapy, to usual treatment. Darolutamide blocks the actions of the androgens (e.g. testosterone) in the tumor cells and in the body. The addition of darolutamide to the usual treatment may better control the cancer and prevent it from spreading.