Start with the work, not the title.
Titles vary between firms. Focus first on the underlying work: building client relationships, taking and managing risk, designing products, explaining markets, or creating quantitative systems.
Know the evidence each role needs.
A strong application connects your experience to the role. Market curiosity, communication, numerical reasoning, coding, and commercial judgement matter in different proportions across different desks.
Keep the first decision broad enough.
You do not need to choose a lifelong specialism before applying. You do need a credible reason for the work, the desk, and the market exposure you are targeting now.