Methyl and methine carbon atoms generate positive signals.
Methylene carbons generate negative signals.
Quaternary carbons generate no signals in DEPT spectra.
Every chemically unique carbon atom generates a separate signal. The coupling to 1H is removed so each appears as a singlet. The three lines at 77.0ppm are from the solvent, CDCl3.
Every chemically unique hydrogen atom generates a unique signal, Their frequencies and splittings give information about their environment. The singlet at 7.25 ppm is from the solvent.