What does a beginner need to know to build an inductive heater?
If you like doing things the really really hard way,
AND don't mind a good dose of 'quite a lot more costly'
AND a large dash of 'somewhat dangerous',
THEN induction heating is definitely the way to go for a beginner. 

All sane and ordinary mere mortals would start with resistance heating, get a good feel for power levels, heat transfer, basic controllers, PID control, temperature sensing and more and THEN, perhaps, look at induction heating.

If having a temperature controllable deep-fryer is you main aim, and vastly stretching your brain, wallet and hours spent on development are only secondary, then you can have something basic using resistance heating working very quickly.

If you really want to pursue induction heating, declare so (ideally with certified copy of sanity accompanying) and we'll see what we can do to assist.