Amazon Brand Approval

Hello, I have a query regarding Amazon Brand Approval. Suppose I aim to list my branded product without a trademark. After extensively researching online videos, my understanding is that to apply for Amazon Brand Approval, my product must be prepared. I need to ensure that I have product and packaging photos ready, prominently featuring my brand name.

My concern is, how can I ascertain if Amazon will approve my brand name? What if the name is already in use on the Amazon platform? Would all my efforts go to waste? I would greatly appreciate it if you could provide some clarification. Thank you!