This page contains information regarding Star Trek: Discovery, and thus may contain spoilers.
The Starfleet Command Training Program, or CTP, was a track to prepare Starfleet officers for the responsibility of commanding a starship and crew. Recommendations and physical-endurance commendation could increase an officer's chances of being accepted into the program. (DIS: "Lethe", "The Wolf Inside")
Cadet Sylvia Tilly shared her aspirations of Captaining a starship someday with Michael Burnham, who took Tilly under her wing and advised her to work towards a physical-endurance commendation to qualify for the program; then to seek out assignment to a Constitution-class starship and work towards First officer track, which would line her up to one day be promoted to Captain. (DIS: "Lethe")
Working to save Paul Stamets, Tilly impressed Commander Saru with her understanding of the spore drive and the mycelial network. On his impression, she asked if he would consider recommending her for the command-training program. Saru noted that if they found their way back to a universe with a training program, he would consider it. (DIS: "The Wolf Inside")
During the Starfleet Medal of Honor award ceremony in 2257, Admiral Katrina Cornwell noted that Ensign Tilly had been accepted into the Starfleet Command Training Program. She was the youngest candidate ever accepted. (DIS: "Will You Take My Hand?", "New Eden") Tilly later contacted her mother for advice on participating in the program, who compared it to a painful incident from Tilly's childhood where she had run away from a physical task she couldn't accomplish - and suggested she ask her step-sister for advice. (ST: "Runaway")
Commander Michael Burnham had completed the Command Training Program, and Tilly made a note on her to do list to speak to her about her time in the program. Commander Saru was Tilly's CTP Director, whom she had to report the results of several of her objectives to. (DIS: "New Eden")