This research study involves pre-operative therapy that is specifically targeted for your type of breast cancer. You will be randomized, which means randomly assigned, to one of the treatment arms. In the 3-week window phase portion of the trial, the treatment arms and the study drugs in each arm are: • Arm A: Tamoxifen • Arm B: Anastrozole • Arm C: Anastrozole + Degarelix After completion of the 3-week window phase, a mandatory research biopsy will be done to determine how your cancer responded to the treatment. In the second phase of the study, the neoadjuvant phase, participants will be randomized to receive 4 months of treatment. Participants from Arm A of the window phase, will be randomized to one of the following treatment arms: • Arm D: Tamoxifen • Arm E: Tamoxifen + Abemaciclib Participants from arms B and C of the window phase will be randomized to one of the following treatments arms: • Arm F: Anastrozole + Degarelix • Arm G: Anastrozole + Degarelix + Abemaciclib After you complete study treatment, you will continue to surgery. The type of surgery you have will be decided by you and your Doctor. After surgery, we would like to keep track of your medical condition every year for up to 10 years.