Sound creation tutorials

Do tutorials show to how to create kicks, bass and other essential sounds or they’re mostly sound sample based?

Sample based mainly. I’d say it’s a bit beyond the scope of the tutorials to show you how to record drum hits etc.

There are however bits on generating Synth sounds. Things like basses, leads etc.

yes, sample based, but useful tips on layering fore example kicks to sound good (tech-trance tut)… but mostly drums, most of pad / synth / bass sounds are synth based, lot of times created from scratch (not using presets)