Professional Subscription Fee

Hi Im from overseas and want to explore the opportunity to sell with our own brand on amazon with FBA. I want to open an seller account and will list in the next 6 month. What happened if I pay the subscription but wont list any items for the next 6 months, will amazon charged me month to month eventhough I haven’t listed anything. Or should I just open an account when Im ready to sell in the future.

Thankyou