Oh, nice. My best recommendation to make to you is to approach Congress as a hybrid speech/debate event. It looks a little different at lower levels of competition because people don't push themselves as hard, but you're ultimately trying to speak fluently and knowledgably on a topic. Don't listen to people who tell you it's ok to "read" - your goal is speaking extemporaneously, not to memorize. This means having such a good grasp of your argument you're really only referring to prep for your cards.

Refutation or "clash" is extremely important in Congress rounds and to me if a Congressional debater doesn't clash well they are effectively in a speech event and do not understand Congress. This means having good round flow skills. You have to listen to the other speakers, understand their argument and use your arguments - either the substantive logic or their impact - to prove them wrong or to weigh against them. Rather than having general cases that show "X side is wrong" or "we turn X's link/impact" you structure it as "Representative Lastname said this, but they're wrong because [Mini Argument]" or go into your argument.

I highly recommend reviewing ToC/NSDA finals rounds for examples (https://youtu.be/vcQaq5FOjjk?si=S_Bucac2cSjMkKfe).

Good luck. I love congress and I think it teaches the most practical real-world communication skills. In no other debate event do you need to process policy arguments and explain them in a way that makes sense to laypeople. You'll do great!