This tutorial comes from This page on Sonicstate.com and explains some essential basics on how FM frequency modulation works.
Most modern virtual analog synthesizers provide at least two operator FM (one modulator and one carrier), including the Access Virus, Alesis ION, Korg Prophecy, Nord Lead and Modular Series, Novation Supernova, and many more.
Some discussion of ratios is included in the video. When using a virtual analog, you probably won’t have an option to set ratios between modulator and carrier. Instead, you’ll set the pitch of the modulator by adjusting its pitch setting. This PDF file has a convenient table for this.
For more tutorials like this you can visit Sonicstate.com