What plan should I get?

Hi folks - I'm composing a digital symphony that's based on a story about a hare and a fox. Trouble is, I haven't really story boarded the action - all I have are a set of very nice starting ChatGPT still images, and just the first (of three) movements composed. . The whole thing will be about 25 mins in length - would the basic sub model be enough for me? I have no idea how quickly I’d use up my credits for a video of this length. And can I/should I do the video in smaller sections? And I don’t plan  to do this frequently….

Thx for advice !!!