Why Modulation is the process of impressing information, such as speech, onto a radio frequency carrier by varying one of the carrier's properties: its amplitude (AM, SSB), its frequency (FM), or its phase. The carrier by itself conveys no information; the audio has to change some characteristic of it so the receiver can recover the speech by demodulating. Every voice mode name, AM, FM, SSB, is just a description of how that modulation is done.
Watch out Oscillation is tempting because an oscillator generates the carrier in the first place, but generating a steady signal is a different step from adding voice information to it. Impedance matching transfers power efficiently between stages, and low-pass filtering removes unwanted high frequency content such as harmonics.
Modulation = MODify the carrier with your voice. Oscillator makes the carrier, modulator puts your words on it.