GnomAD has publicly available VCF files that have variant data gathered from over 15k individuals. For a university project, I want to randomly select 1k of these individuals and get the variant data belgoning to them only.

I am very new to bioinformatics in general and upon checking VCF files and how they work, my current conclusion is that this task is not achievable through filtering the vcf file in any way since variants in these files have no direct connection to the genomes they were found in (no array of individual IDs in a variant entry that show which individuals had this variant).

But this task was given to me by a professor whom I believe is competent to realize the task was impossible if it is like I thought, so is there something I am missing?

How can I go about randomly selecting a 1000 individuals from this 15 000 pool, and then generating a new VCF file with the data from these selected 1000?

Are there any fields that show which individuals genome samples showed a spesific variant entry in the VCF file?