Text classification and text extraction best practices

Hi there!
I’ve just started to learn how to work with api and currently i’m working on 2 projects(one is text extraction and the other is classification)
So in first project i have medical data that includes transcriptions column, from which api should extract the age of the patient, treatment and ICD code. Now the question is how is it better to give my data to API? Now i’ve just extracted the transcription, converted to a list and gave in prompt, but i’m sure there are better ways to do this. Is it better to give it in one list all together or one transcription at the time? (which way is more accurate, fast and/or cost efficient).
In the second mini project i have list with names that api should classify by gender. Here i have same question. Also since those are singe turn requests do i need to use both user and system roles or can just give everything in one?
I’ll be glad to get any best practices and advise that will make this whole topic clearer for me. Thank you so much for your time!)