The most common and most likely answer to this crossword clue is the 10 letter word STAIRCASES
I've seen this crossword clue in Independent
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More clues leading to the result STAIRCASES
Buddy explains!

The straight part
We know that "Ways to reach the next level" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ways to reach the next level = staircases.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does STAIRCASES mean?
STAIRCASES noun- A flight of stairs; a stairway.
- A connected set of flights of stairs; a stairwell.
- A set of locks (enclosed sections of waterway) mounted one above the next.