I know the heat and pressure will make it so we could never find this out but for the gas giants how far down would we need the pressure to be for it to be like walking on solid ground even though it's 'gas'?

If I dropped a nuke on Jupiter would it burn away the gas and not exist any more?

Like if I'm a rogue hermit state like dprk and I get the tech and science to send a thermonuclear warhead at Jupiter. . It burns up during entry and the warhead explodes and Jupiter burns like the failed sun it is?