Step-by-step explanation:
An independent clause refers to a group of words (found in a sentence) that contains both a subject and a predicate. And the predicate of a sentence is simply a verb explaining what the subject does.
Therefore, here are all the words that make up the two independent clauses below:
Subject = Erik Killmonger
Predicate = signed up for knitting lessons; (he) wanted to make his own sweaters.