Sentence 1:
Corrected Sentence: Upon entering the room, the detective noticed several possible clues.
Comma Rule: Use a comma after an introductory clause or phrase.
Sentence 2:
Corrected Sentence: I did extra chores all week long because I wanted to get a later curfew over the weekend.
Comma Rule: No comma is needed in this case, as the clause following is a dependent clause that is essential to the meaning of the sentence. However, if the sentence were to be split into two independent clauses, a comma would be necessary.
(Note: The second sentence is already correct as it is.)