Attach custom post type to postings

How would lone go about associating a custom post type to job postings?

I would like to have the Company related Job Listing data setup as a post type (entered once).
Ideally, when creating a new job listing admin users could just select a Company (instead of having to enter every individual company field for every listing) and have this populate on the front end.

If there isn’t an off-the-shelf solution that allows this, some general pointers on how one would implement it would be helpful.

Thanks so much for any info on this!