How to Dispute Collections?

I have a couple medical collections from 2016..

At the time I didn’t have medical insurance & I wanted to see if anyone here had some advice on how to dispute them?

I’ve obviously never done it before & I’m not sure where to get started.

Quick edit - I was seeking advice on how to dispute because that’s what I was suggested to do by the people I’ve asked.. but after reading the comments, these are debts I do owe so my best bet is to just make payment arrangements.

I appreciate your feedback!