(not) anything; nothing (with negative verb)
Used with a negative verb to mean 'nothing' or 'not ... anything'. The negative verb is required.
There is nothing in the fridge.
He didn't say anything.
and everything else; and all (in ...も何も pattern)
Used in the pattern ...も何も to mean '... and everything else' or '... and all'. Emphasizes that the preceding item is included along with other related things.
He threw away his job and everything else and went on a trip.
(not) at all; (not) especially (with ...なくてもいい etc.)
Used with expressions like ...なくてもいい or ...ことはない to mean 'not at all', 'not especially', or 'not to that extent'. Softens the necessity or obligation.
There's no need to apologize at all.
There's no need to rush especially.