I'm willing to create a zvs induction heater but I have some questions

Hello there!

I want to create a ZVS induction heater but I don't fully understand yet how the coils need to be driven.
I haven't started yet with building it, but I already wanted to check if the induction heating effect was working, so I
connected a coil onto my high current DC blockwave generator and nothing really happens.
it's a PWM controller which switches between 0V and the applied voltage.

Is it because it sends DC signals to the coil, and the magnetic field goes into saturation?
If so, I added a capacitor in series with the coil, to filter out the DC component
but now nothing happens. There is nearly no current flowing trough the circuit.

I'd also need some information on what influences the intensity of the heating?
Is it the Amp*Turns that matters?
because we're using high frequency here to lower the required current; but if it's amp*turns then we need the current to be as high as possible. So something's wrong there in the way I thought this works :/
I do know how the material gets heated. (by eddy currents that increase if the flux alternates at higher amplitudes)

also, at what voltage should the coil be switched?
does the voltage matter? Should I use something like 12v? 40v? or even 2v of I only need high current?

I do know that the use of the high frequency is to increase skin effect in the material to be heated, but what other reasons are there for using such high frequency?
Is it also because eddy currents will increase at higher frequency? If so, why would this happen?

A lot of questions indeed :) but I'm not going to start copy-pasting the circuit, and then just being happy that it's working.
I also need to know Why it works, and how!

Thanks in advance,

Do you know what inductance is ?