When an employee refers someone, that’s the golden endorsement. Referrals make up for less than 10% of applications, but 20-50% of eventual hires.
As for practice questions, concentrate on the Arrays and Strings, Linked Lists, Stacks and Queues, Trees and Graphs, Objected-Oriented Design, Recursion, and Sorting sections.
Important content should be higher up. For a student, the order of importance is usually Education > Experience > Projects > Skills.