Teenager Wants to Get into trading..

Hi all, Im a teen (16) And I want to get into trading. I have played with paper accounts in the past and have made good money, I would consider myself financially literate and knowledgeable. I would say that I have an idea of the market and what not. I do know that for minors you would need a custodial account. I would also want to get into algo trading but I know that requires a 25k deposit? I am not sure, and I would like clarification... My main goals first and foremost is open an account whether it be custodial or not (and if it is what are the limitations) and start investing, and using profits for algo trade. I want to know if this is possible. What is the best platform to go with? eg ameritrade, schwab, I also am interested in researching day trading and its capabilities.. Thank you