In English, prepositions are often little more than "noise words" that convey little or no information. Sometimes they're required or encouraged for syntactic reasons, but there are many contexts where native speakers disagree over which, if any, preposition(s) should be used in any given context.
I specifically highlighted that optional pluralising 's' above because it might not be obvious to all learners that native speakers often chain together multiple optional prepositions - and this doesn't always have much (or any) effect on the meaning of the containing utterance. Consider, for example,...
1: Get on down to the basement!
2: Get down to the basement!
3: Get on to the basement!
4: Get to the basement!
...where all four versions effectively mean the same thing. Some people might not like all of them, but they all occur in natural speech. In these examples, the only preposition that's actually required is the final to (Get the basement! with no preposition is never acceptable).
Doubtless there are even more extreme examples of such "cascading optional prepositions", but one that comes to mind is...
5: I'm going off out down to the pub
...where again, only to is actually required. But most permutations (using any number of the other three prepositions, in various different sequences) could in fact occur, from at least some native speakers.
Regarding OP's second example, I must say that I personally feel the (totally unnecessary) use of prepositions there looks a bit ignorant / "affected". It's much simpler to use none at all (except the syntactically required about)...
Why do you wanna talk about death?
I don't want to overstate my initial point that these words convey little or no information. In any given context, they may at least impart a slight "nuance". Thus with my first three examples, on has overtones of get along (get moving, shift yourself!), and down has direct semantic relevance (the basement is lower than speaker's current location). But any such nuances are often vague and/or unimportant.