Getting started and looking for good resources

I have just gotten started using ElasticSearch and NEST (.NET client).

There is a lot of information around, but much of it seems to assume some
base knowledge, and I'm not sure where to go for that. I was wondering if
anyone could suggest resources that might help me get up to speed. For
instance, it isn't clear how filters and queries are nested/combined. Would
understanding Lucene concepts be the best way to start?

I have a fairly straightforward use case...a series of optional query
params to my REST API that I will parse and use to retrieve the IDs of
matching documents - no score necessary...but so far I can't seem to sort
out how to get there.

Thanks in advance,
Cork

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