No, "homework" does not need a capital letter unless it is at the beginning of a sentence or used in a title.
No, "thrush" does not need a capital letter unless it is at the beginning of a sentence or part of a proper noun.
NO
no
not really
No
The word king does not need a capital letter. The reason the words April, California, and Renae need capital letters at the beginning is that they are proper nouns.
s
YES
farm
No
Denmark is not in the UK. It is a separate country. The capital of Denmark is Copenhagen. The capital of the UK is London.