Without arrays, tracking ten scores means int score1, score2. score10;. That is messy. With arrays, you write int scores[10]; and you are done. Arrays make processing easy with loops.
Instead of ten statements to sum scores, loop from 0 to 9 and add scores[i]. Whether you have 10 or 1000 elements, the code stays the same. You can pass arrays to functions and reuse logic.
Write one function to find the maximum, then call it whenever needed. This keeps code clean.