Opening a Roth IRA: Lump sum or divided contribution?

Hello! I’m planning on opening a roth ira account with fidelity soon (this month) just have a few questions.

Is it better to do a lump sum (~$6000) to invest now or divide the contributions? For next year,2024, I’m planning to divide contributions but this year to catch up I’m not sure if I should lump sum the whole limit.